## FANDOM

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This page guides the presentation of numbers, dates, times, measurements, currencies, coordinates, and similar material in articles. Its aim is to promote clarity and cohesion; this is especially important within an article. The goal is to make the whole encyclopedia easier and more intuitive to use.

Where this manual provides options, consistency should be maintained within an article unless there is a good reason to do otherwise. The Arbitration Committee has ruled that editors should not change an article from one guideline-defined style to another without a substantial reason unrelated to mere choice of style, and that revert-warring over optional styles is unacceptable.[1] If discussion cannot determine which style to use in an article, defer to the style used by the first major contributor.

## General notes

### Quotations, titles, etc.

Quotations, titles of books and articles, and similar "imported" text should be faithfully reproduced, even if they employ formats or units inconsistent with these guidelines or with other formats in the same article. If necessary, clarify via [bracketed interpolation], article text, or footnotes.

• It is acceptable to change other date formats in the same article to provide consistency, so long as those changes would otherwise be acceptable.

### Non-breaking spaces

Guidance on the use of non-breaking spaces ("hard spaces") – &nbsp;, {{nbsp}}, &thinsp;, {{thinsp}} – is given in some sections below; {{nowrap}} may also be useful in controlling linebreaks in some situations. Not all situations in which hard spaces or {{nowrap}} may be appropriate are described. For further information see Wikipedia:Manual of Style § Non-breaking spaces and Wikipedia:Line-break handling.

## Chronological items

### Statements likely to become outdated

Except on pages updated regularly (e.g. the "Current events" portal), terms such as Template:FormattingError, Template:FormattingError, Template:FormattingError, Template:FormattingError, Template:FormattingError, and Template:FormattingError should usually be avoided in favor of phrases such as Template:FormattingError, Template:FormattingError, and Template:FormattingError. For current and future events, use phrases like Template:FormattingError or Template:FormattingError to signal the time-dependence of the information. Using {{as of|2017}} will produce the text Template:FormattingError and adds the article to a category flagging it for periodic review. A full date is specified with {{as of|2017|07|24}}. However, do not replace Template:FormattingError with {{as of|2005}} because some information (the beginning of 2005) would be lost; in such circumstances, use advanced features of {{as of}} such as {{as of|2005|alt=since the beginning of 2005}}.

Relative-time expressions are acceptable for very long periods, such as geological epochs: Template:FormattingError

### Time of day

Context determines whether the 12- or 24-hour clock is used; in both, colons separate hours, minutes and seconds (e.g. Template:FormattingError or Template:FormattingError).

The numerical elements of times-of-day are figures (Template:FormattingError) rather than words (Template:FormattingError) though conventional terms such as Template:FormattingError and Template:FormattingError are acceptable (taking care, with the latter, to avoid possible date ambiguity in constructions such as Template:FormattingError).

#### Time zones

Give dates and times appropriate to the time zone where an event took place. For example, the date of the attack on Pearl Harbor should be December 7, 1941 (Hawaii time/Template:Zwspdate). Give priority to the place at which the event had its most significant effects; for example, if a hacker based in China attacked a Pentagon computer in the US, use the time zone for the Pentagon, where the attack had its effect. In some cases the best solution may be to add the date and time in Coordinated Universal Time (UTC). For example:
•   Template:FormattingError

Alternatively, include just the UTC offset:

•  Template:FormattingError

Rarely, the time zone in which a historical event took place has since changed; for example, China to 1949 was divided into five time zones, whereas all of modern China is UTC+8. Similarly, the term "UTC" is not appropriate for dates before this system was adopted in 1960;[2] Universal Time (UT) is the appropriate term for the mean time at the prime meridian (Greenwich) when it is unnecessary to specify the precise definition of the time scale. Be sure to show the UTC or offset appropriate to the clock time in use at the time of the event, not the modern time zone, if they differ.

### Dates, months and years

These requirements do not apply to dates in quotations or titles; . Special rules apply to citations; .

#### Formats

Acceptable date formats
General use Only where brevity is helpful (refs,[3] tables, infoboxes, etc.) Comments
Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError A comma follows the year unless followed by other punctuation:[4] Template:Unordered list
Template:FormattingError Template:FormattingError Omit year only where there is no risk of ambiguity: Template:Unordered list
Template:FormattingError Template:FormattingError
No equivalent for general use Template:FormattingError Use yyyy-mm-dd format only with Gregorian dates from 1583 onward.[5]
Template:FormattingError Template:FormattingError

Unacceptable date formats (except in external titles and quotes)
Template:FormattingError Template:FormattingError Do not add a dot to the day or to an abbreviated month[7]
Template:FormattingError Template:FormattingError or Template:FormattingError
Template:FormattingError
Template:FormattingError
Months are capitalized
Template:FormattingError
Template:FormattingError
Template:FormattingError
Do not use ordinals (Template:FormattingError, Template:FormattingError, Template:FormattingError, etc.)
Template:FormattingError
Template:FormattingError
Do not "zero-pad" month or day, except in all-numeric (yyyy-mm-dd) format
Template:FormattingError Template:FormattingError
Template:FormattingError Do not use separators other than hyphen
Template:FormattingError Do not abbreviate year to two digits
Template:FormattingError
Template:FormattingError
Do not use dd-mm-yyyy, mm-dd-yyyy or yyyy-dd-mm formats, as they are ambiguous for some dates[8]
Template:FormattingError
Template:FormattingError
Template:FormattingError
Template:FormattingError
Template:FormattingError
Template:FormattingError Do not use these formats.
Template:FormattingError No comma between month and year
Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError Comma required between day and year
Template:FormattingError
Template:FormattingError
Template:FormattingError Do not abbreviate year
Template:FormattingError Template:FormattingError Roman numerals are not normally used for dates
Template:FormattingError Template:FormattingError Years and days of the month are not normally written in words
Template:FormattingError
Template:FormattingError
Template:FormattingError Template:FormattingError Do not zero-pad years
Template:FormattingError Template:FormattingError Use "in the year" only where needed for clarity
##### Consistency

Shortcut:
• MOS:DATEUNIFY
• the format used in the article body text,
• an abbreviated format from the "Acceptable date formats" table, provided the day and month elements are in the same order as in dates in the article body, or
• the format expected in the citation style being used (however, all-numeric date formats other than yyyy-mm-dd must still be avoided).
For example, a single article might contain one, but only one, of:
Template:FormattingError
Template:FormattingError
(among other possibilities).
• Access and archive dates in an article's citations should all use the same format, which may be:
• the format used for publication dates in the article;
• the format expected in the citation style adopted in the article (e.g. Template:FormattingError); or
• yyyy-mm-dd
For example, a single article's citations might contain either of the following:
Template:FormattingError
Template:FormattingError
When a citation style does not expect differing date formats, it is permissible to normalize publication dates to the article body text date format, and/or access/archive dates to either, with date consistency being preferred.
##### Strong national ties to a topic
• Articles on topics with strong ties to a particular English-speaking country should generally use the date format most commonly used in that nation. For the United States this is (for example) Template:FormattingError; for most other English-speaking countries it is Template:FormattingError
• Articles related to Canada may use either format with (as always) consistency within each article.
• In some topic areas the customary format differs from the usual national one: for example, articles on the modern U.S. military use day-before-month, in accordance with U.S. military usage.
##### Retaining existing format
• If an article has evolved using predominantly one format, the whole article should conform to it, unless there are reasons for changing it based on strong national ties to the topic or consensus on the article's talk page.
• The date format chosen by the first major contributor in the early stages of an article should continue to be used, unless there is reason to change it based on strong national ties to the topic or consensus on the article's talk page.
• Where an article has shown no clear sign of which format is used, the first person to insert a date is equivalent to "the first major contributor".

#### Julian and Gregorian calendars

A date can be given in any appropriate calendar, as long as it is (at the minimum) given in the Julian calendar or the Gregorian calendar or both, as described below. For example, an article on the early history of Islam may give dates in both Islamic and Julian calendars. Where a calendar other than the Julian or Gregorian is used, the article must make this clear.

• Current events are dated using the Gregorian calendar.
• Dates of events in countries using the Gregorian calendar at that time are given in the Gregorian calendar. This includes some of the Continent of Europe from 1582, the British Empire from 14 September 1752, and Russia from 14 February 1918 (see Gregorian calendar).
• Dates before 15 October 1582 (when the Gregorian calendar was first adopted in some places) are normally given in the Julian calendar. The Julian day and month should not be converted to the Gregorian calendar, but the start of the Julian year should be assumed to be 1 January (see below for more details).
• Dates for Roman history before 45 BC are given in the Roman calendar, which was neither Julian nor Gregorian. When (rarely) the Julian equivalent is certain, it may be included.
• For dates in early Egyptian and Mesopotamian history, Julian or Gregorian equivalents are often uncertain. Follow the consensus of reliable sources, or indicate their divergence.

The dating method used should follow that used by reliable secondary sources (or if reliable sources disagree, that used most commonly, with an explanatory footnote).

At some places and times, the new year began on a date other than 1 January. For example, in England and its colonies until 1752, the year began on Annunciation Day, 25 March; see the New Year article for other styles. In writing about historical events, however, years should be assumed to have begun on 1 January (see the example of the execution of Charles I in "Differences in the start of the year"); if there is reason to use another start-of-year date, this should be noted.

If there is a need to mention Old or New Style dates in an article (as in the Glorious Revolution), a footnote should be provided on the first usage, stating whether the New Style refers to a start of year adjustment or to the Gregorian calendar (it can mean either).

#### Ranges

• A pure year–year range is written (as is any range) using an en dash (&ndash; or {{ndash}}) not a hyphen or slash; this dash is usually unspaced (that is, with no space on either side); and the range's end year is usually given in full:
•   Template:FormattingError;  Template:FormattingError (not Template:FormattingError;  Template:FormattingError)
Template:Hanging indent
• The ending year in a range may be abbreviated to two digits (Template:FormattingError, but never Template:FormattingError or Template:FormattingError) in the case of two consecutive years and in infoboxes and tables where space is at a premium. (Use a single format consistently in any given table column, both for aesthetic reasons and so that data sorts properly.)
• Articles in certain topic areas may use two-digit ending years if there is a very good reason, such as matching the established convention of reliable sources in that topic area. Similarly, the slash notation (Template:FormattingError) may be used to signify a fiscal year or other special period, if that convention is used in reliable sources.
• Other "pure" ranges use an unspaced en dash as well:
• If at least one of the items on either side of the en dash is in a mixed format (containing two or more of day, month, year); carries a modifier such as Template:Circa; or otherwise contains a space; then a spaced en dash ({{snd}}) is used:
Template:FormattingError
Template:Hanging indent
Template:FormattingError
Template:Hanging indent
Or use an en dash: (unspaced) Template:FormattingError;  (spaced) Template:FormattingError.
•  {{age|1989|7|23}} returns: Template:FormattingError
•  {{age|1989|7|23}}-year-old returns: Template:FormattingError
•  {{age|1989|7|23}} years old returns: Template:FormattingError

#### Uncertain, incomplete, or approximate dates

•   Template:FormattingError
•   Template:FormattingError
•   Template:FormattingError
• Where both endpoints of a range are approximate, c. should appear before each date:
•   Template:FormattingError (not Template:FormattingError)
•   Template:FormattingError (not Template:FormattingError)
• Where birth/death limits have been inferred from known dates of activity:
•   Template:FormattingError
•   Template:FormattingError
•   Template:FormattingError
• When a person is known to have been active ("flourishing") during certain years, Template:FormattingError, [[Floruit|fl.]], or {{fl.}} may be used:
•   Template:FormattingError
The linked forms should not be used on disambiguation pages, and "active" followed by the range is a better alternative for artists, soldiers and other persons with an occupation.
• When a date is known to be either of two years (e.g. from a regnal or AH year conversion, or a known age at death):
•   Template:FormattingError

### Other

#### Seasons

Unambiguous alternatives include Template:FormattingError;  Template:FormattingError;  Template:FormattingError;  Template:FormattingError.

• For a social era or cultural phenomenon associated with a particular decade:

## Numbers

### Numbers as figures or words

Generally, in article text:

• "billion" and "trillion" are understood to represent their short-scale values of 109 (1,000,000,000) and 1012 (1,000,000,000,000), respectively. Keep this in mind when translating articles from non-English Wikipedias, or using material from non-English sources.
• Template:FormattingError (unspaced) or Template:FormattingError (unspaced) respectively may be used for "million" or "billion" after a number, when the word has been spelled out at the first occurrence (e.g., Template:FormattingError).
• SI prefixes and symbols, such as Template:Xtn (Template:Xtn) and Template:Xtn (Template:Xtn), should be restricted to scientific, engineering, and technical uses.
• Sometimes, the variety of English used in an article may necessitate the use of a numbering system other than the Western thousands-based system. For example, the South Asian numbering system is conventionally used in South Asian English. In those situations, link the first spelled-out instance of each quantity (e.g. [[crore]], which yields crore). (If no instances are spelled out, provide a note after the first instance directing the reader to the article about the numbering system.) Also, provide a conversion to Western numbers for the first instance of each quantity, and provide conversions for subsequent instances if they do not overwhelm the content of the article. For example, write Template:FormattingError. Group digits in Western thousands-based style (e.g., Template:FormattingError; not Template:FormattingError); see § Delimiting (grouping of digits), below. (Note that the variety of English does not uniquely determine the method of numbering in an article. Other considerations, such as conventions used in mathematics, science and engineering, may also apply, and the choice and order of formats and conversions is a matter of editorial discretion and consensus.)

Notes and exceptions:

•  Template:FormattingError, not Template:FormattingError.
•  Template:FormattingError, not Template:FormattingError
•  Template:FormattingError, even though 3 would normally be given as three; or Template:FormattingError (or two hundred and six in British English), even though two hundred six would normally be given as 206); but not Template:FormattingError.
• Avoid beginning a sentence with figures:
•   Not Template:FormattingError,
but Template:FormattingError or Template:FormattingError.
•   Not Template:FormattingError (nor Template:FormattingError – because comparable numbers should be both written in words or both in figures) but Template:FormattingError

### Fractions and ratios

•   $\textstyle\frac{1}{2}$ – markup: <math>\textstyle\frac{1}{2}[/itex]
•   Template:FormattingError – markup: {{sfrac|2}}
•   Template:FormattingError – markup: 1/2

### Decimals

#### Grouping of digits

• Digits should be grouped and separated either by commas or narrow gaps (never a period/full point).
Grouping with commas
Grouping with narrow gaps
• Digits are grouped both sides of the decimal point (e.g.  Template:FormattingError,  Template:FormattingError,  Template:FormattingError).
• Digits are generally grouped into threes. Right of the decimal point, usual practice is to have a final group of four instead of a lone digit (e.g.  Template:FormattingError  or  Template:FormattingError). In mathematics-oriented articles long strings may be grouped into fives (e.g.  Template:FormattingError).
• This style is especially recommended for articles related to science, technology, engineering or mathematics.
• Markup: Templates {{val}} or {{gaps}} may be used to produce this formatting. Note that use of any space character in numbers, including non-breaking space, is problematic for screen readers. (See §Non-breaking spaces.) Screen readers read out each group of digits as separate numbers (e.g.  30&thinsp;000  is read as "thirty zero zero zero".)
• Delimiting style should be consistent throughout a given article.
• Either use commas or narrow gaps, but not both in the same article.
• Either group the thousands in a four-digit number or do not, but not mixed use in the same article.
• However, grouping by threes and fives may coexist.

### Scientific and engineering notation

Markup: {{val}} and {{e}} may be used to format exponential notation.

### Uncertainty and rounding

• Where explicit uncertainty information (such as a margin of error) is available and appropriate for inclusion, it may be written in various ways:
•  Template:FormattingError
•  Template:FormattingError (not used with scientific notation)
•  Template:FormattingError
•  Template:FormattingError (equivalent to Template:FormattingError)[9]
•  Template:FormattingError
Markup: {{+-}}, {{su}}, and {{val}} may be used to format uncertainties.
• Where explicit uncertainty is unavailable (or is unimportant for the article's purposes) round to an appropriate number of significant digits; the precision presented should usually be conservative. Precise values (often given in sources for formal or matter-of-record reasons) should be used only where stable and appropriate to the context, or significant in themselves for some special reason.
•   Template:FormattingError
but Template:FormattingError
•   Template:FormattingError (not Template:FormattingError – an official figure unlikely to be accurate at full precision)
but Template:FormattingError (unusual case in which the full-precision official population figure is helpful to readers)
•   Template:FormattingError (likely that accurate and precise figures were determined)
•   Template:FormattingError (unlikely that any precise number can be accurate, even if an official figure is issued)
or Template:FormattingError (in reporting conflicting information, give detail sufficient to make the contrast intelligible)
•   Template:FormattingError (where the actual figure was \$8,462,247.63) Template:FormattingError
• The number of decimal places should be consistent within a list or context (Template:FormattingError, not Template:FormattingError), unless different precisions are actually intended.
• It may sometimes be appropriate to note the lack of uncertainty information, especially where such information is normally provided and necessary for full interpretation of the figures supplied.
•   Template:FormattingError
• The {{undue precision}} template may be added to figures appearing to be overprecise.
• Avoid using "approximately", "about", and similar terms with figures that have merely been approximated or rounded in a normal and expected way, unless the reader might otherwise be misled.
•   Template:FormattingError ( – heights are conventionally reported only to the nearest inch, even though greater precision may be available in principle)
but Template:FormattingError ("about" because here the precise value is unknown, with substantial uncertainty)

## Units of measurement

### Unit choice and order

For details on when and how to provide a conversion, see § Unit conversions.

Quantities are typically expressed using an appropriate "primary unit", displayed first, followed, when appropriate, by a conversion in parentheses e.g. Template:FormattingError. For details on when and how to provide a conversion, see the section § Unit conversions. The choice of primary units depends on the circumstances, and should respect the principle of "strong national ties", where applicable:

• In non-scientific articles relating to the United States, the primary units are US customary, e.g. Template:FormattingError.
• In non-scientific articles relating to the United Kingdom, the primary units for most quantities are metric or other internationally used units,[10] except that:
• UK engineering-related articles, including those on bridges and tunnels, generally use the system of units that the topic was drawn up in (but road distances are given in imperial units, with a metric conversion – see next bullet);
• the primary units for distance/Template:Zwsplength, speed and fuel consumption are miles, miles per hour, and miles per imperial gallon (except for short distances or lengths, where miles are too large for practical use);
• the primary units for personal height and weight are feetTemplate:Zwsp/inches and stones/Template:Zwsppounds;
• imperial pints are used for quantities of draught beer/Template:Zwspcider and bottled milk;
• In all other articles, the primary units chosen will be SI units, non-SI units officially accepted for use with the SI, or such other units as are conventional in reliable-source discussions of the article topic (such as revolutions per minute (rpm) for angular speed, hands for heights of horses, et cetera).

Special considerations:

• Quantities set via definition (as opposed to measured quantities) should be given first in the units used in the definition, even if this makes the structure of presentation inconsistent: Template:FormattingError.
• This may benefit from a slightly non-standard structure, such as Template:FormattingError. In this sort of case, using Template:Xtn can help make clear which is the statutory, exact value.
• Nominal quantities (e.g. Template:FormattingError) require consideration of whether the article is concerned with the item's actual dimensions or merely with its function. In some cases only the nominal quantity may suffice; in others it may be necessary to give the nominal size (often in non-SI units), the actual size in non-SI units, and the actual size in SI units.
• Whenever a conversion is used, ensure that the precision of the converted quantity in the article is comparable to the precision of the value given by the source (see § Unit conversions).
• Where the article's primary units differ from the units given in the source, the {{convert}} template's |order=flip flag can be used; this causes the original unit to be shown as secondary in the article, and the converted unit to be shown as primary: {{convert|200|mi|km|order=flip}}Template:FormattingError

### Unit names and symbols

Definitions:
• Examples of unit names: foot, meter, kilometer.
• Examples of unit symbols: ft, m, km.
• Unit names and symbols should follow the practice of reliable sources.
• In prose, unit names should be given in full if used only a few times, but symbols may be used when a unit (especially one with a long name) is used repeatedly, after spelling out the first use (e.g. Template:FormattingError).
• Where space is limited, such as in tables, infoboxes, parenthetical notes, and mathematical formulas, unit symbols are preferred.
• Units unfamiliar to general readers should be presented as a name–symbol pair on first use, linking the unit name (Template:FormattingError).
• Ranges use unspaced en dash ({{ndash}}) if only one unit symbol is used at the end (e.g. Template:FormattingError), and spaced en dash ({{snd}}) if two symbols are used (e.g. Template:FormattingError); ranges in prose may be specified using either unit symbol or unit names, and units may be stated either after both numerical values or after the last (e.g. Template:FormattingError, Template:FormattingError, Template:FormattingError and Template:FormattingError are all acceptable).
• Length–width, length–width–height and similar dimensions may be separated by the multiplication sign (×) or the word Template:Xtn.
• With the multiplication sign, each number should be followed by a unit name or symbol (if appropriate):
•  Template:FormattingError, not , Template:FormattingError nor
•  Template:FormattingError
•  Template:FormattingError
General guidelines on unit names and symbols
Aspect Guideline 11px Acceptable 11px Unacceptable
Spelling The spelling of certain unit names (some of which are listed in § Specific units, below) varies with the variety of English followed by the article.
Format Do not spell out numbers before unit symbols ... Template:FormattingError Template:FormattingError
... but words or numerals may be used with unit names.
Values with no accompanying unit are usually given in figures. Template:FormattingError Template:FormattingError
Write unit names and symbols in upright (roman) type, except where emphasizing in context. Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError
Template:FormattingError
Unit names are given in lower case except: where any word would be capitalTemplate:Shyized, or where otherwise specified in the SI brochure[11] or this Manual of Style.Template:Clarify Template:FormattingError
Except as listed in the "Specific units" table below, unit symbols are uncapiTemplate:ShytalTemplate:Shyized unless they are derived from a proper name, in which case the first letter (of the base unit symbol, not of any prefix) is capitalized.[12] Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError
Unit symbols are undotted. Template:FormattingError Template:FormattingError
In general, a normal ("breaking") space is used between a number and a unit name, but a nonbreaking space ({{nbsp}} or &nbsp) between a number and a unit symbol (or {{nowrap}} may be used). Certain symbols with which no space is used are shown in the "Specific units" table below.
To form a value and a unit name into a compound adjective use a hyphen or hyphens ...
... but a non-breaking space (never hyphen) separates a value and unit symbol. Template:FormattingError
Plurals SI unit names are pluralized by adding the appropriate Template:FormattingError or Template:FormattingError suffix ... Template:FormattingError, Template:FormattingError
... except for these irregular forms. Template:FormattingError, Template:FormattingError Template:FormattingError
Template:FormattingError, Template:FormattingError Template:FormattingError
Template:FormattingError, Template:FormattingError Template:FormattingError
Template:FormattingError, Template:FormattingError
Some non-SI units have irregular plurals. Template:FormattingError, Template:FormattingError Template:FormattingError
Template:FormattingError, Template:FormattingError (unusual) Template:FormattingError
Unit symbols (in any system) are identical in singular and plural.
Powers Format exponents using <sup>...</sup>, not special characters. Template:FormattingError (Markup: km<sup>2</sup>) Deprecated markup: km&#178;
Or use Template:Xtn or Template:Xtn (after the unit being modified). Template:FormattingError Template:FormattingError
For areas or volumes only, Template:Xtn or Template:Xtn may be used (before the unit being modified). Template:FormattingError
Template:FormattingError
Template:Xtn or Template:Xtn may be used with US customary or imperial units, but not with SI units. Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError
Products Indicate a product of unit names with either a hyphen or a space.
Indicate a product of unit symbols with &middot; or &nbsp; (Note: {{middot}} is not equivalent to &middot;.)
Exception: In some topic areas such as power engineerTemplate:Shying, certain products take neither space nor &middot;. Follow the practice of reliable sources in the article's topic area.
To pluralize a product of unit names, pluralize only the final unit. (Unit symbols are never pluralized.) Template:FormattingError Template:FormattingError
Ratios,
Rates,
Densities
Indicate a ratio of unit names with Template:Xtn. Template:FormattingError Template:FormattingError
Indicate a ratio of unit symbols with a forward slash (/), followed by either a single symbol or a parenthesized product of symbols – do not use multiple slashes; or use −1, −2, etc.
To pluralize a ratio of unit names, pluralize only the numerator unit. (Unit symbols are never pluralized.)
Some of the special forms used in the imperial and US customary systems are shown here ...
... but only the slash or negative exponent notations are used with SI (and other metric) units. Template:FormattingError
Template:FormattingError
Prefixes Prefixes should not be separated by a space or hyphen. Template:FormattingError
Prefixes are added without contraction, except as shown here: Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError
The Template:Xtn, Template:Xtn, Template:Xtn, and Template:Xtn prefixes should generally be avoided; exceptions include centimetre, decibel, hectolitre, hectare, and hectopascal. Template:FormattingError
Do not use [[wikt:M#Number|Template:FormattingError]] for 103, Template:FormattingError for 106, or Template:FormattingError for 109 (except as noted elsewhere on this page for Template:Xtn and Template:Xtn, e.g. for monetary values) Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError
Template:FormattingError Template:FormattingError
Mixed
units
Mixed units are traditionally used with the imperial and US customary systems
... and in expressing time durations ...
… but are not normally used in SI. Template:FormattingError
No comma. Template:FormattingError Template:FormattingError

Note to table:

1. Only use this format if it is clear from the context whether this means hours and minutes (H:MM) or minutes and seconds (M:SS).

### Specific units

• The following table lists only units that need special attention.
• The SI Brochure[11] should be consulted for guidance on use of other SI and non-SI units.
Guidelines on specific units
Group Name Symbol Comment
Length,
Speed
inch Template:FormattingError Do not use &prime; (Template:FormattingError), &Prime; (Template:FormattingError), apostrophe/Template:Zwspsingle quote (Template:FormattingError) or double quote (Template:FormattingError).
foot Template:FormattingError
foot per second Template:FormattingError (not Template:FormattingError)
hand Template:FormattingError or Template:FormattingError Equal to 4 inches; used in measurement of horses. A dot may be followed by additional inches e.g. Template:FormattingError indicates 16 hands 2 inches.
knot Template:FormattingError (not Template:FormattingError or Template:FormattingError)
• metre
• meter (U.S.)
Template:FormattingError
micron Template:FormattingError (not Template:FormattingError) Markup: &mu;m  Link to micrometre (for which micron is a synonym) on first use.
astronomical unit Template:FormattingError (not Template:Xtn is the most commonly used unit symbol for the astronomical unit, both in popular and professional astronomical articles, and is hence also used on Wikipedia, although some organizations, including the BIPM[11] and IAU,[13] recommend Template:Xtn.
mile Template:FormattingError In nautical and aeronautical contexts use Template:FormattingError rather than mile to avoid confusion with nautical mile.
mile per hour Template:FormattingError
nautical mile Template:FormattingError or Template:FormattingError
Volume,
Flow
• cubic centimetre
• cubic centimeter (U.S.)
Template:FormattingError Markup: cm<sup>3</sup>
Template:FormattingError Non-SI symbol used for certain engine displacements; link to Cubic centimetre on first use.
imperial fluid ounce Template:FormattingError Template:Xtn or Template:Xtn (or Template:Xtn) must be specified; Template:Xtn or Template:Xtn must be specified, except with  gallon. (Without Template:Xtn, ounce is ambiguous – versus avoirdupois ounce or troy ounce – and US pint or US quart are ambiguous – versus US dry pint or US dry quart.)
imperial fluid pint Template:FormattingError
imperial fluid quart Template:FormattingError
imperial gallon Template:FormattingError
US fluid ounce Template:FormattingError
US fluid pint Template:FormattingError
US fluid quart Template:FormattingError
US gallon Template:FormattingError
cubic foot Template:FormattingError (not Template:FormattingError) Write Template:FormattingError, Template:FormattingError or Template:FormattingError, not Template:FormattingError.
cubic foot per second Template:FormattingError (not Template:FormattingError)
• litre
• liter (U.S.)
Template:FormattingError or Template:FormattingError The symbol l ("el") in isolation (i.e. not in such forms as ml) is easily mistaken for the digit 1 or the capital letter I ("eye").
Mass,
Force,
Density,
Pressure
long ton Template:FormattingError Spell out in full.
short ton Template:FormattingError
pound per square inch Template:FormattingError
Template:FormattingError
troy ounce Template:FormattingError Template:Xtn or Template:Xtn must be specified. Articles about precious metals, black powder, and gemstones should always specify whether ounces and pounds are avoirdupois or troy.
troy pound Template:FormattingError
carat Template:FormattingError Used to express masses of gemstones and pearls.
Purity carat or karat Template:FormattingError or Template:FormattingError A measure of purity for gold alloys. (Do not confuse with the unit of mass with the same spelling.)
Time second Template:FormattingError Do not use &prime; (Template:FormattingError), &Prime; (Template:FormattingError), apostrophe (Template:FormattingError) or quote (Template:FormattingError) for minutes or seconds. Use Template:Xtn for "minute" only where there is no danger of confusion with meter, as in the hours–minutes–seconds formats for time durations described in the Unit names and symbols table.
minute Template:FormattingError
hour Template:FormattingError
year Template:FormattingError Use Template:Xtn only with an SI prefix multiplier (Template:FormattingError, not Template:FormattingError).
Template:FormattingError or Template:FormattingError See § Long periods of time for all the affected units.

Information,
Data

byte Template:FormattingError or Template:FormattingError
bit per second Template:FormattingError (not Template:FormattingError or Template:FormattingError)
byte per second Template:FormattingError or Template:FormattingError
Angle
arcminute Template:FormattingError Prime: ′. Markup: &prime;  (not apostrophe/Template:Zwspsingle quote Template:FormattingError). No space between numerals and symbol
arcsecond Template:FormattingError Double prime: ″. Markup: &Prime;  (not double-quote Template:FormattingError). No space between numerals and symbol
degree Template:FormattingError Markup: &deg;  (not masculine ordinal Template:FormattingError or ring Template:FormattingError). No space between numerals and symbol

Temperature

degree Template:FormattingError Markup: &deg;. Nonbreaking space between numerals and symbol: 12{{nbsp}}&deg;C, not 12&deg;C nor 12&deg;{{nbsp}}C
degree Celsius (not degree centigrade) Template:FormattingError (not Template:FormattingError)
Energy
• calorie
• small calorie
• gram calorie
Template:FormattingError In certain subject areas, calorie is conventionTemplate:Shyally used alone. Articles following this practice should specify on first use whether the use refers to the small calorie or to the kilocalorie (large calorie). Providing conversions to SI units (usually calories to joules or kilocalories to kilojoules) may also be useful. A kilocalorie (Template:FormattingError) is 1000 calories. A calorie (small calorie) is the amount of energy required to heat 1 gram of water by 1 °C. A kilocalorie is therefore also a kilogram calorie.
• kilocalorie
• large calorie
• kilogram calorie
• (not Calorie – can be ambiguous)
Template:FormattingError

#### Quantities of bytes and bits

In quantities of bits and bytes, the prefixes Template:Xtn (symbol Template:Xtn or Template:Xtn), Template:Xtn (Template:Xtn), Template:Xtn (Template:Xtn), Template:Xtn (Template:Xtn), etc., are ambiguous. They may be based on a decimal system (like the standard SI prefixes), meaning 103, 106, 109, 1012, etc., or they may be based on a binary system, meaning 210, 220, 230, 240, etc. The binary meanings are more commonly used in relation to solid-state memory (such as RAM), while the decimal meanings are more common for data transmission rates, disk storage and in theoretical calculations in modern academic textbooks. Template:Bit and byte prefixes Follow these recommendations when using these prefixes in Wikipedia articles:

• Following the SI standard, a lower-case Template:FormattingError should be used for "kilo-" whenever it means 1000 in computing contexts, whereas a capital Template:FormattingError should be used instead to indicate the binary prefix for 1024 according to JEDEC. (If, under the exceptions detailed further below, the article otherwise uses IEC prefixes for binary units, use Template:FormattingError instead).
• Do not assume that the binary or decimal meaning of prefixes will be obvious to everyone. Explicitly specify the meaning of k and K as well as the primary meaning of M, G, T, etc. in an article ({{BDprefix}} is a convenient helper). Consistency within each article is desirable, but the need for consistency may be balanced with other considerations.
• The definition most relevant to the article should be chosen as primary for that article, e.g. specify a binary definition in an article on RAM, decimal definition in an article on hard drives, bit rates, and a binary definition for Windows file sizes, despite files usually being stored on hard drives.
• Where consistency is not possible, specify wherever there is a deviation from the primary definition.
• Disambiguation should be shown in bytes or bits, with clear indication of whether in binary or decimal base. There is no preference in the way to indicate the number of bytes and bits, but the notation style should be consistent within an article. Acceptable examples include:
•  Template:FormattingError
•  Template:FormattingError
•  Template:FormattingError

The IEC prefixes Template:Xtn (symbol Template:Xtn), Template:Xtn (Template:Xtn), Template:Xtn (Template:Xtn), etc., are generally not to be used except:[14]

• when the majority of cited sources on the article topic use IEC prefixes;
• in a direct quote using the IEC prefixes;
• when explicitly discussing the IEC prefixes; or
• in articles in which both types of prefix are used with neither clearly primary, or in which converting all quantities to one or the other type would be misleading or lose necessary precision, or declaring the actual meaning of a unit on each use would be impractical.

### Unit conversions

Where English-speaking countries use different units for the same quantity, follow the "primary" quantity with a conversion in parentheses: Template:FormattingError; Template:FormattingError. In science-related articles, however, supplying such conversion is not required unless there is some special reason to do so.

• Where an imperial unit is not part of the US customary system, or vice-versa – and in particular, where those systems give a single term different definitions – a double conversion may be appropriate: Template:FormattingError (markup: {{convert|80|kg|lb stlb}}); Template:FormattingError (markup: {{convert|5|L/100km|mpgus mpgimp|abbr=on}}).
• Generally, conversions to and from metric units and US or imperial units should be provided, except:
• When inserting a conversion would make a common or linked expression awkward (Template:FormattingError).
• When units are part of the subject of a topic – nautical miles in articles about the history of nautical law (Template:FormattingError), SI units in scientific articles (Template:FormattingError), yards in articles about American football – it can be excessive to provide conversions every time a unit occurs. It might be best to note that this topic will use the units (possibly giving the conversion factor to another familiar unit in a parenthetical note or a footnote), and link the first occurrence of each unit but not give a conversion every time it occurs.
• Converted quantity values should use a level of precision similar to that of the source quantity value, so Template:FormattingError, not Template:FormattingError. Small numbers may need to be converted to a range where rounding would cause a significant distortion, so Template:FormattingError, not Template:FormattingError. Be careful especially when your source has already converted from the units you're now converting back to. This may be evidenced by multiples of common conversion factors in the data, such as 160 km (from 100 miles). See false precision.
• Conversion templates can be used to convert and format many common units, including {{convert}}, which includes non-breaking spaces.
• In a direct quotation, always retain the source units. Any conversions can be supplied either in the quote itself (in square brackets, following the original measurement) or in a footnote. See footnoting and citing sources.
• {{Units attention}} may be added to articles needing general attention regarding choice of units and unit conversions.

## Currencies and monetary values

### Currency symbols

• In general, the first mention of a particular currency should use its full, unambiguous signifier (e.g. Template:FormattingError), with subsequent references using just the appropriate symbol (e.g. Template:FormattingError), unless this would be unclear. Exceptions:

### Formatting

• Exceptions may occur in tables and infoboxes where space is limited e.g. Template:FormattingError. It may be appropriate to wikilink such uses, or add an explanatory note.

### Conversions

• Conversions of less-familiar currencies may be provided in terms of more familiar currencies – such as the US dollar, euro or pound sterling – using an appropriate rate (which is often not the current exchange rate). Conversions should be in parentheses after the original currency, rounding to avoid false precision (two significant digits is usually sufficient, as most exchange rates fluctuate significantly), with at least the year given as a rough point of conversion rate reference; e.g. Template:FormattingError, not Template:FormattingError.
• For obsolete currencies, provide an equivalent (formatted as a conversion) if possible, in the modern replacement currency (e.g. decimal pounds for historical pre-decimal pounds-and-shillings), or a US-dollar equivalent where there is no modern equivalent.
• In some cases it may be appropriate to provide a conversion accounting for inflation or deflation over time. See {{Inflation}} and {{Inflation-fn}}.

## Common mathematical symbols

• The Insert menu below the editing window gives a more complete list of math symbols, and allows symbols to be inserted without the HTML encoding (e.g. &divide;) shown here.
• Spaces are placed to left and right when a symbol is used with two operands, but no space with one operand.
• Use {{var}} or <var>...</var> for variable names: {{var|base}} + {{var|ht}} and <var>base</var> + <var>ht</var> both produce base + ht.
• The {{nbsp}} and {{nowrap}} templates may be used to prevent awkward linebreaks.
Common mathematical symbols
Plus /
positive
x + y x + y
+y +y
Minus /
negative
xy x &minus; y Do not use hyphen (Template:FormattingError) or dashes (Template:FormattingError
y &minus;y
Plus-minus /
minus-plus
41.5 ± 0.3 41.5 &plusmn; 0.3
−(±a) = ∓a &minus;(&plusmn;a) = &#8723;a
Multiplication,
cross
x × y x &times; y Do not use the letter Template:FormattingError to indicate multiplication. However, an unspaced Template:FormattingError may be used as a substitute for "by" in common terms such as [[4x4|Template:FormattingError]].
Division, obelus x ÷ y x &divide; y
Equal / equals x = y x = y
Not equal xy x &ne; y
Approx. equal Template:Pi ≈ 3.14 <code>{{pi}} &asymp; 3.14</code>
Less than x < y x &lt; y
Less or equal xy x &le; y
Greater than x > y x &gt; y
Greater or equal xy x &ge; y

## Geographical coordinates

For draft guidance on, and examples of, coordinates for linear features, see Wikipedia:WikiProject Geographical coordinates/Linear.
Quick guide:

Geographical coordinates on Earth should be entered using a template to standardise the format and to provide a link to maps of the coordinates. As long as the templates are adhered to, a robot performs the functions automatically.

First, obtain the coordinates. Avoid excessive precision.

Two types of template are available:

• {{coord}} offers users a choice of display format through user styles, emits a Geo microformat, and is recognised (in the title position) by the "nearby" feature of Wikipedia's mobile apps and by external service providers such as Google Maps and Google Earth, and Yahoo.
• Infoboxes such as {{Infobox settlement}}, which automatically emit {{Coord}}.

The following formats are available.

• For degrees only (including decimal values): {{coord|dd|N/S|dd|E/W}}
• For degrees/minutes: {{coord|dd|mm|N/S|dd|mm|E/W}}
• For degrees/minutes/seconds: {{coord|dd|mm|ss|N/S|dd|mm|ss|E/W}}

where:

• dd, mm, ss are the degrees, minutes and seconds, respectively;
• N/S is either N for northern or S for southern latitudes;
• E/W is either E for eastern or W for western longitudes;
• negative values may be used in lieu of S and W to denote Southern and Western Hemispheres

For example:

For the city of Oslo, located at 59° 55′ N, 10° 44′ E:

{{coord|59|55|N|10|44|E}} – which becomes Script error

For a country, like Botswana, less precision is appropriate:

{{coord|22|S|24|E}} – which becomes Script error

Higher levels of precision are obtained by using seconds:

{{coord|33|56|24|N|118|24|00|W}} – which becomes Script error

Coordinates can be entered as decimal values

{{coord|33.94|S|118.40|W}} – which becomes Script error

Increasing or decreasing the number of decimal places controls the precision. Trailing zeros should be used as needed to ensure that both values have the same level of precision.

London Heathrow Airport, Amsterdam, Jan Mayen and Mount Baker are examples of articles that contain geographical coordinates.

Generally, the larger the object being mapped, the 'less precise the coordinates should be. For example, if just giving the location of a city, precision greater than 100 meters is not needed unless specifying a particular point in the city, for example the central administrative building. Specific buildings or other objects of similar size would justify precisions down to 10 meters or even one meter in some cases (1′′ ~15 m to 30 m, 0.0001° ~5.6 m to 10 m).

The final field, following the E/W, is available for attributes such as type:, region:<code>, or <code>scale:<code> (the codes are documented at Template:Coord/doc#Coordinate parameters). 

When adding coordinates, please remove the <code>{{coord missing}} tag from the article, if present.

Templates other than {{coord}} should use the following variable names for coordinates: lat_d, lat_m, lat_s, lat_NS, long_d, long_m, long_s, long_EW.