Wikipedia:Manual of Style/Dates and numbers

This Manual of Style, like all style guides, attempts to encourage consistency and ease of reading. The guidelines here are just that: guidelines are not inflexible rules; one way is often as good as another, but if everyone does it the same way, Wikipedia will be easier to read, write and edit.

New contributors are reminded that clear, informative and unbiased writing is always more important than presentation and formatting. Wikipedians are not required to follow any of these rules. (See Wikipedia:Editing policy.)

Dates

Years, decades, and centuries

This section describes how to link to years, decades and centuries. See sections which follow, regarding when such linking is appropriate.

See Anno Domini for a discussion on what is meant by AD and BC notation, and Common Era for a discussion on what is meant by CE and BCE notation.

A page title that is just a positive whole number is always a year. Pages also exist for days of the year, decades, centuries and even millennia. The formats for references to years are:

• 474
  • [[474]]
• 474 BC (note no periods) or 474 BCE
  • [[474 BC]] or [[474 BCE]]
• 18th century or eighteenth century (Note: century is not capitalized, and "1700s" is not a century, but a decade)
  • [[18th century]] or [[eighteenth century]]
• 10th century BC or 10th century BCE (or "tenth")
  • [[10th century BC]] or [[10th century BCE]]
• 1830s (Not 1830's)
  • [[1830s]]
• December 1983 (note that December is not linked)
  • December [[1983]]
• 320s BC or 320s BCE
  • [[320s BC]] or [[320s BCE]]

Articles for the year 500 BC and earlier should be redirected to the relevant decade. Articles for the year 1700 BC and earlier should be redirected to the relevant century. Articles for the year 4000 BC and earlier should be redirected to the relevant millennium.

Note that the first century BC was from 100 BC to 1 BC (there was no year 0) so 1700 BC would be the first year of the 17th century BC, 1800 BC would be the first year of the 18th century BC, etc. Similarly, 4000 BC was the first year of the fourth millennium BC, not the last year of the fifth millennium BC.

When only an approximate date is available the abbreviation "c." (Latin: circa, "about") may be used; see the example at Rameses III below. When a date is uncertain—because the sources are unreliable—that fact should be noted and, if possible, the source specified. For example, "according to Livy, the Roman Republic was founded in 509 BC", or "The Mahabharata is traditionally said to have been composed in 1316 BCE".

Dates containing a month and a day

If a date includes both a month and a day, then the date should normally be linked to allow readers' date preferences to work, displaying the reader's chosen format. The day and the month should be linked together, and the year should be linked separately if present. For example:

• Month and day
  • [[February 17]] → February 17
  • [[17 February]] → 17 February

• Day, month, and year
  • [[February 17]], [[1958]] → February 17, 1958
  • [[17 February]] [[1958]] → 17 February 1958
  • [[1958]]-[[02-17]] : 1958-02-17
  • [[1958-02-17]]: 1958-02-17

To create a date that is linked but not converted, use a piped link with alternate text, for example "[[17 February|17 February]]". This should only be done with good reason, such as in a direct quotation. In this case, it may be preferable not to link the date at all, as the link does not then help with readers' date preferences.

In article titles, dates will not be converted.

There are some exceptions to the rule that dates with a month and a day should always be linked:

• Using the date formatting feature in section headers complicates section linking, see date formatting.

• On disambiguation pages, only the disambiguated articles should be linked, not explanatory text.

Partial dates

If the date does not contain both a month and a day, date preferences do not apply: linking or not linking the date will make no difference to the text that the reader sees. So when considering whether such a date should be linked or not, editors should take into account the usual considerations about links, including the recommendations of Wikipedia:Only make links that are relevant to the context.

There is consensus among editors that bare month and day names should not be linked unless there is a specific reason that the link will help the reader to understand the article. There is less agreement about links to years. Some editors believe that links to years are generally useful to establish context for the article. Others believe that links to years are rarely useful to the reader and reduce the readability of the text. Another possibility is to link to a more specific article about that year, for example [[2006 in sports|2006]], although some people find this unintuitive because the link leads to an unexpected destination.

Examples of links which do not respond to readers' date preferences:

• Year only: [[1974]] → 1974.
• Month only: [[April]] → April. Generally should not be linked.
• Century: [[20th century]] → 20th century.
• Decade: [[1970s]] → 1970s.
• Year and month: [[April]] [[1974]] → April 1974.
• New year and month: [[April 2000]] → April 2000. Currently articles only exist for combinations from the year 2000 to current; other month-year combinations redirect to the article for the year.
• Day of the week (with or without other date elements): [[Tuesday]] → Tuesday. Generally should not be linked.

Date formats related to topics

If the topic itself concerns a specific country, editors may choose to use the date format used in that country. This is useful even if the dates are linked, because new users and users without a Wikipedia account do not have any date preferences set, and so they see whatever format was typed. For topics concerning the UK, Australia, Ireland, New Zealand, most member states of the Commonwealth of Nations, and most international organizations such as the United Nations, the formatting is usually [[17 February]] [[1958]] (no comma and no "th"). In the United States and Canada, it is [[February 17]], [[1958]]. Elsewhere, either format is acceptable. See Wikipedia:Manual of Style#National varieties of English for more guidance.

ISO date formats

ISO 8601 dates, for example 1958-02-17, are unambiguous. However, they are not common in English prose, and are therefore unfamiliar to many readers. As such, they should generally not be used in normal prose. This applies even if they are in a link: although the software will convert such dates according to users' date preferences (for example, [[1958-02-17]] → 1958-02-17), new users and unregistered users do not have any date preferences set, and will therefore see the unconverted ISO 8601 date.

This advice only applies to dates in normal prose. ISO 8601 dates may sometimes be useful elsewhere; for example, they are useful in lists, tables, for dates of birth/death, for conciseness and ease of comparison.

Incorrect date formats

• Do not use numbers to express a month, except in ISO 8601 format. Always express a month as a whole word (e.g. "February" not "2"). Do not use abbreviations like "Feb" unless space is precious in a table, infobox, or the like.
• Do not use two digits to express a year unless at the end of a range, e.g., "1970–87" (the same for BC). In all other cases, use four digits for years and decades after AD 999 (the same for BC). Using the less formal two-digit form for a decade is acceptable when not ambiguous; for example, when referring to the decade of the 20th century known as "the eighties", use "1980s" or, less often, "the '80s", not just "80s".

• Use consistent date formatting throughout an article, unless there's a good reason to vary it.

• Do not use ordinal suffixes:
  • Incorrect: "February 14th" and "14th February"
  • Correct: "February 14" and "14 February"

• Do not use articles:
  • Incorrect: "the 14th of February"
  • Correct: "February 14" and "14 February"

• Do not put a comma or the word "of" between a month and year:
  • Incorrect: "December, 1945" and "December of 1945"
  • Correct: "December 1945"

• Do not use an apostrophe to indicate a decade:
  • Incorrect: 1970's
  • Correct: 1970s

Direct quotations

An important exception to these guidelines is that direct quotations—the word-for-word reproduction of a written or oral text—should not be altered to conform to the Wikipedia "Manual of Style". In other words, a paragraph such as the (fictional) quotation from a newspaper report is fine as is:

"Tony Blair, responding to critics in his party, said 'The world has totally changed since the 11th of September.' He was echoing earlier sentiments by Lord Ronald McDonald, who said that 'nine-eleven' was the day that the American public woke up to the reality of terrorism."

Dates of birth and death

• Charles Darwin (12 February 1809–19 April 1882)
  • Locations should be included in the biography portion of the body article. For example, "(February 12 1809 in Shrewsbury, Shropshire, England–April 19 1882 in Downe, Kent, England)" should be separated to "(February 12 1809–April 19 1882) … He was born in Shrewsbury, Shropshire, England … He died in Downe, Kent, England".
• Socrates (470–399 BC) (or "BCE")
  • When only the years are known.
• Serena Williams (born September 26 1981)
  • For a person still living at the time the article was written.
  • Notice that the form is NOT "(September 26 1981–)"
• Offa (died 26 July 796)
  • When the date of birth is unknown.
• Genghis Khan (c.1162–August 18, 1227)
  • When the date of birth is known approximately.
• Dionysius Exiguus (c.470–c.540)
  • When dates of birth and death are known approximately.
• Robert Menli Lyon (born 1789, date of death unknown)
  • When the date of death is unknown, but the person is certainly now dead.
• Rameses III (reigned c. 1180 BCE–c. 1150 BCE)
  • When only the dates of the reign are known and only approximately.
• Osmund (fl. 760–772)
  • When the person was known to have been alive (flourishing) at certain dates. Note that [[floruit|fl.]] is used to link to floruit, in case the meaning isn't familiar.
• Aethelwalh (fl. c.660–685)
  • Here the person was known to have been alive approximately as early as 660, and to have died in 685.

Note the use of "c." rather than "circa", "ca." or a question mark.

Ranges of dates are given with a spaced or unspaced hyphen or en dash (–). See Wikipedia:Manual of Style (dashes).

Seasons

Because the seasons are reversed in each hemisphere—while areas near the equator tend to have just wet and dry seasons—neutral wording should be used to describe times of the year, such as "in early 1990", "in the second quarter of 2003", "around September" or an exact date, rather than references to seasons, unless there is some particular need to do so (e.g., "the autumn harvest"). It is ambiguous to say that Apollo 11 landed on the Moon in the summer of 1969—whose summer? However, quoted references to seasons should not be changed.

Eras

• Both the BCE/CE era names and the BC/AD era names are acceptable, but be consistent within an article.

• Normally you should use plain numbers for years in the Anno Domini/Common Era, but when events span the start of the Anno Domini/Common Era, use AD or CE for the date at the end of the range (note that AD precedes the date and CE follows it). For example, [[1 BC]]–[[1|AD 1]] or [[1 BCE]]–[[1|1 CE]].

• In articles about prehistory, if you use BP (before present) or MYA (million years ago), expand these abbreviations when you first use them, as most readers will be unfamiliar with them.

• When either of two styles are acceptable it is inappropriate for a Wikipedia editor to change from one style to another unless there is some substantial reason for the change. For example, with respect to English spelling as opposed to American spelling it would be acceptable to change from American spelling to English spelling if the article concerned an English subject. Revert warring over optional styles is unacceptable; if the article is colour rather than color, it would be wrong to switch simply to change styles as both are acceptable. See also Wikipedia:Requests for arbitration/Jguk.

Different calendars

You can give dates in any appropriate calendar, as long as you also give the date in either the Julian or Gregorian calendar, as described below. For example, an article on the early history of Islam may give dates in both the Islamic calendar and the Julian calendar.

• Current events should be given in the Gregorian calendar.
• Dates before the adoption of the Gregorian calendar on 1582-10-15 should usually be 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 taken to be 1 January (see below for more details).
• Dates of events in countries using the Gregorian calendar should be given in the Gregorian calendar. This includes much of Europe from 1582, the British Empire from 1752-09-14, Russia from 1918-02-14, and so on (see the Gregorian calendar article).

Other dates are ambiguous. Your options for this period are:

• Give the dates in the Julian calendar only. This means that the dates will match the dates in the primary sources for that period. If you do this you should indicate that the dates are in the Julian calendar.
• Convert the dates to the Gregorian calendar. This means that events in different countries can be correlated.
• Give dates in both calendars, for example, William Shakespeare died on 1616-04-23 (Old Style)/1616-05-03 (New Style).

At some places and times, dates other than 1 January were used as the start of the year. The most commonly encountered convention is the Annunciation Style used in Britain and its colonies in which the year started on 25 March. See the New Year article for a list of other styles. You should always convert dates so that they correspond with years starting on 1 January. If it is important to preserve consistency with primary sources, you may give the date in the original style, but then you must also give the date in the modern style. For example, Elizabeth I of England died on 1602-03-24 (Old Style)/1603-03-24 (New Style). Although this would correspond to 3 April 1603 if fully converted into the Gregorian calendar, the month and day of a British event are normally not converted.

Times

Time formatting

Context will determine whether the 12-hour or 24-hour clock notation should be used. In either case, the colon is used to separate hours, minutes and seconds.

Times in the 12-hour clock end with lower case "a.m." or "p.m.". These suffixes generally cannot be omitted, except that "noon" and "midnight" should be used instead of "12 p.m." and "12 a.m."; some readers find the latter ambiguous. Beware that even "12 midnight" does not unambiguously distinguish between midnight at the start and end of a given date.

24-hour clock times have no a.m./p.m./noon/midnight suffix. Discretion may be used to determine if the hour has a leading zero. 00:00 refers to midnight at the start of a day and 12:00 refers to noon. (In addition, 24:00 can be used for midnight at the end of a given date, which can be useful to state the end of a time interval.)

Examples:

12-hour clock	Not	24-hour clock	Not
2 p.m.	2pm	14:00	14.00
2:34 p.m.	2.34 PM	14:34	1434
12:04:38 a.m.	12.04 38″ A.M.	00:04:38 or 0:04:38
noon	12 noon	12:00

Time zones

When writing a date, first consider where the event happened and use the time zone there. For example, the date of the Attack on Pearl Harbor should be December 7, 1941 (Hawaii time/date). If it is difficult to judge where, consider what is significant. For example, if a vandal based in Japan attacked a Pentagon computer in the United States, use the time zone for the Pentagon, where attack had its effect.

If you know it, include the UTC date and time of the event in the article, indicating that it's UTC.

Numbers

Numbers

Very large numbers may be divided up by commas every three places (e.g.: 2,900,000), starting from the decimal separator in both directions. (This is different from the SI/ISO 31-0 notation style, where punctuation marks are not used, but as an option, a thin space may be inserted every three places.) In scientific contexts, scientific notation is preferred. Large round numbers are generally assumed to be approximations; it is necessary to qualify with "about" or a similar term where the statement would otherwise be misleading.

A period (".") must be used as the decimal separator, separating the integer part from the fractional part.

For numbers between minus one and plus one, include the leading 0 ("0.02", not ".02").

The minus sign has two representations. One is the normal hyphen-minus ("-") available on every computer keyboard (twice on those with numeric keypad); the other ("−") is most easily entered as −.

Percentages

• The word percent or per cent is commonly used to indicate percentages in the body of an article. The symbol % may be more common in scientific or technical articles, or in complex listings. Be consistent throughout an article.

• Use the symbol % with a numeral for a percentage in a such locations as tables and infoboxes. There is no space between the numeral and the symbol %.

Numbers in words

• Whole numbers from zero to ten are spelled out as words in the body of an article. Use numerals in tables and infoboxes.

• Numbers above ten may be written out if they are expressed in two or fewer words, except in tables and infoboxes. Example: "sixteen", "eighty-four", "two hundred", "twenty million" but "3.75", "544", "21 million".

• Within a context or a list, style should be consistent. Example: There were 5 cats, 12 dogs, and 32 birds. or There were five cats, twelve dogs, and thirty-two birds.

• It is considered awkward for a numeral to be the first word of a sentence: recast the sentence or spell the number out.

• Fractions standing alone should be spelt out unless they occur in a percentage. If fractions are mixed with whole numbers, use numerals.

• Billion is understood as 10⁹ in the United States, Canada and most of the rest of the English-speaking world. (In most Germanic and Romance languages, it means 10¹².) See the detailed discussion in English-language numerals, long and short scales. International monetary institutions generally recognize a billion as equaling 10⁹ when it relates to expenditure, GDP, deficits.

Natural number

Natural number has two meanings:

• positive integer, or
• non-negative integer (including zero).

When referring to such numbers, explicitly use one of the above phrases rather than "natural numbers", unless it does not matter which interpretation is chosen.

Ranges

Sometimes numbers and dates are expressed in ranges, such as "14–17" for the numbers 14 to 17. It is often preferable to write this out—for example, ""fourteen through seventeen" (US and Canada) or "from 14 to 17") to avoid confusion with "fourteen minus seventeen", which is expressed with spaces, as "14 − 17".

Traditionally, ranges of numbers and dates are given with an en dash (type – or click the – button below the edit window). Therefore, many Wikipedians support using this style exclusively. However, some sources now use spaced or unspaced hyphens, at least online, and some Wikipedians believe that these hyphens should not be changed to en dashes.

See Wikipedia:Manual of Style (dashes) for more information.

Non-base-ten numbers

For numbers in bases other than base ten,

• In computer-related articles, use the C programming language prefixes—that is, 0x for hexadecimal and 0 for octal. For binary, use 0b. It may be a good idea to include a note at the top of the page about these prefixes.
• In all other articles, use subscript notation. For example: 137₉, 241₆, 2A9₁₂, A87D₁₆ (use _and).
• For base eleven and higher, use whatever symbols are conventional for that base. A common convention is to use A–Z for digits ten to thirty five. Where applicable, use uppercase rather than lowercase letters: 0x5AB3, not 0x5ab3.

Units of measurement

Wikipedia articles are intended for people anywhere in the world. Try to make articles simple to read and translate.

• Conversions should generally be included and not be removed.
• If editors cannot agree about the sequence of units, put the source value first and the converted value second.
• If for some reason the choice of units is arbitrary, choose SI units as the main unit, with other units in parentheses. For subjects dealing with the United States, it might be more appropriate to use U.S. measurements first, i.e. mile, foot, U.S. gallon.
• Spell out units in the text.
• Use digits and unit symbols for values in parentheses and for measurements in tables. For example, "a pipe 100 millimetres (4 in) in diameter and 16 kilometres (10 mi) long" or "a pipe 4 inches (100 mm) in diameter and 10 miles (16 km) long".
• Converted values should use a similar level of precision as the source value. For example, "the Moon is 380,000 kilometres (240,000 mi) from Earth", not "(236,121 mi)".
• Use standard abbreviations when using symbols. For example, metre is m, kilogram is kg, inch is in (not " or ″), foot is ft (not ' or ′), and pound is lb (not #).
• Do not append an s for plurals of unit abbreviations. For example, kg, in, yd, lb not kgs, ins, yds, lbs.
• Some non-metric units have more than one version. Be specific. For example, U.S. gallon or imperial gallon rather than just gallon. Similarly, use nautical mile or statute mile rather than just mile in aviation, space, sea and in some other contexts.
• Put a space between the value and the unit symbol, for example "25 kg" not "25kg". Preferably, use   for the space (25 kg) so that it does not break lines.

Magnitude prefixes

Binary prefixes

Multiple-byte units
Decimal Value Metric 1000 kB kilobyte 10002 MB megabyte 10003 GB gigabyte 10004 TB terabyte 10005 PB petabyte 10006 EB exabyte 10007 ZB zettabyte 10008 YB yottabyte 10009 RB ronnabyte 100010 QB quettabyte	Binary Value IEC Memory 1024 KiB kibibyte KB kilobyte 10242 MiB mebibyte MB megabyte 10243 GiB gibibyte GB gigabyte 10244 TiB tebibyte TB terabyte 10245 PiB pebibyte — 10246 EiB exbibyte — 10247 ZiB zebibyte — 10248 YiB yobibyte — — —
Orders of magnitude of data

In computing, binary prefixes can be used to quantify large numbers where powers of two are more useful than powers of ten. They are commonly written and pronounced identically to the SI prefixes, but each successive prefix is multiplied by 1024 (2¹⁰) rather than 1000 (10³).

Avoiding confusion

Using the prefixes kilo-, mega-, giga-, etc., and symbols like kB, MB, GB, etc., in the binary sense can cause serious confusion. In January 1999, the International Electrotechnical Commission introduced in IEC 60027 the prefixes kibi-, mebi-, gibi-, etc., and the symbols Ki, Mi, Gi, etc. to specify binary multiples of a quantity. They have since been officially adopted by several other organizations such as IEEE and NIST.

• Prefixes for binary multiples - NIST
• When is a kilobyte a kibibyte? And an MB an MiB? - IEC

The use of the new binary prefix standards in the Wikipedia is not required, but is recommended for use in all articles where binary capacities are used. In articles where the precise byte capacities are important to description, the binary prefix should be used with binary capacities and the SI prefix should be used with decimal capacities (and should be noted as decimal if not immediately clear). If a contributor changes an article's usage from kilo- etc. to kibi- etc. where the units are in fact binary, that change should be accepted. However, because they are less familiar, binary unit prefixes such as MiB should be linked at least once per article to avoid confusion. Link as [[Mebibyte|MiB]] to avoid a disambiguation page.

Do not change all SI prefixes to IEC prefixes in computing contexts, only those that are actually being used in a binary sense. For example, do not change a "160 GB HDD" to "158.69 GiB" (still less "160 GiB"), but you can change 512 MB RAM to 512 MiB RAM where it is important to do so. (Notice that the number does not change because the SI prefix was used in a binary sense. Both usages are acceptable, but the MiB reference is less ambiguous.)

Measures that typically use decimal multiples:

• Capacities of hard disk drives and some storage media
• Computer network and bus speeds

Measures that typically use binary multiples:

• Memory and cache sizes
• Some storage media

Examples

• The highest score recorded for the Deuces High pinball game was 11,933,750.
• The hippopotamus stands 1.5 metres (5 ft) at the shoulders and weighs between 2,700 and 4,500 kilograms (6,000–9,900 lb).
  • The [[hippopotamus]] stands [[1 E0 m|1.5 metres]] (5 ft) at the shoulders and weighs between [[Orders of magnitude (mass)|2,700 and 4,500 kilograms]] (6,000–9,900 lb).
• … between 2.7 and 4.5 tons.
• The first sub-four-minute mile was run by Roger Bannister.
• The 155-millimetre diameter projectile offers a wide range of options for battlefield usage.
• 10² = 100
  • 10² = 100
• A large number such as 156,234,000,000,000,000,000,000,000,000 can be concisely recorded as 1.56234{{e|29}}, and a small number such as 0.0000000000234 can be written as 2.34×10⁻¹¹.
• The computer has a 160 GB HDD and 512 MiB of RAM.

See orders of magnitude and the talk page there for ongoing, possibly resolved debate on which style of exponent notation to use for large numbers.

Geographical coordinates

Geographical coordinates on Earth should be entered using a template. This standardizes the format. It also provides a link to a page with several links to maps of the coordinates, and is part of a new way to handle geographic information in Wikipedia.

Depending on the form of the coordinates, three template formats are available. For just degrees, use d mode:

{{coor d|DD|N/S|DD|E/W|}}

For degrees/minutes, use dm mode:

{{coor dm|DD|MM|N/S|DD|MM|E/W|}}

For degrees/minutes/seconds, use dms mode:

{{coor dms|DD|MM|SS|N/S|DD|MM|SS|E/W|}}

Where:

• DD, MM, SS are the degrees, minutes, seconds listed one by one
• N/S is either N or S, depending on which hemisphere
• E/W is either E or W, depending on which hemisphere

Examples

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

{{coor dm|59|55|N|10|44|E|}}

which becomes 59°55′N 10°44′E

For a country, like Botswana, the d mode is more appropriate:

{{coor d|22|S|24|E|}}

Which becomes 22°S 24°E

For higher accuracy, use the dms mode:

{{coor dms|33|56|24|N|118|24|00|W|}}

Which becomes 33°56′24″N 118°24′00″W

Examples of articles using geographical coordinates:

• Airports: London Heathrow Airport
• Cities: Amsterdam
• Islands: Jan Mayen
• Mountains: Mount Baker

Decimal degrees, minutes, or seconds

• degrees can be specified with decimals, in d mode
• minutes can be specified with decimals, in dm mode
• seconds can be specified with decimals, in dms mode

Example:

{{coor d|12.0433|S|77.0283|W|}}

Which becomes 12.0433°S 77.0283°W / -12.0433; -77.0283

Attributes

The final field, following the E/W, is available for specification of attributes, such as type, region and scale. For more information, see the geographical coordinates WikiProject.

Note

Due to planned enhancements in functionality, the above template concept is subject to change. As long as the above templates are adhered to, any necessary changes will be performed automatically by a robot.

Currency

Competing/overlapping proposals: Wikipedia:Manual of Style (dates and numbers)#Currency and/or Wikipedia:WikiProject Numismatics/Style#Article titles.

Abbreviation

• Use the most commonly used English symbol or code (eg US$ or USD), and link to the relevant article at the first few usage.
• If there is no common English abbreviation or symbol, use the ISO 4217 standards.

Spacing

The spacing between the currency symbol and the number is optional, ie US$100 or US$ 100 is fine, but please be consistent throughout the article.

Country

In country-specific articles such as Economy of Australia, use the currency symbol specific to the country by default (AU$ or AUD etc. in this example) unless you have good reasons to use others (eg if your are comparing AUD with USD, it is no problem to use USD even in country-specific articles). Place an italicized note at the top of the article to make this clear to both readers and editors. Type it like :''All amounts in the article are expressed in [[Australian dollars]] unless otherwise specified.''

However it may be wise to use the full form of currency symbol even in country-specific articles (ie AU$ but not $ in this example). While a careful editor will keep the default currency in mind, a careless editor may not. Under the Australian-specific article, a careful editor will use $ to mean AU$, but a careless editor may use $ to mean US$. As it is a wikipedia policy to minimise ambiguity, using the full form helps to spot the problems and clear things up.

In articles which are not country specific such as Wealth, you may use United States dollar by default unless you have good reasons to use others. Type it like [[US$]]100 or [[USD]]123, but not $123 since it can lead to ambiguity and confusion.

Conversions

Conversions can be made into other currencies that are more familiar to most readers, such as the euro or United States dollar. Conversions should be in parentheses after the original currency, with the month and year given as a rough point of reference, for example, 1,000 Swiss francs (approx. US$763 in Jul 2005), rounding to the nearest whole unit.

Examples

Good style

• US$123 or USD123

• A$123 or AU$123 or AUD123
• C$123 or CA$123 or CAD123
• € 123 or EUR 123
• NZ$ 123 or NZD 123
• GB£ 123 or GBP 123
• CN¥ 123 or CNY 123 or RMB 123 or 123 Renminbi (¥)

Bad style

• $123 — Although it is generally assumed to be in United States dollar, different readers and editors may have different assumptions. This will lead to ambiguity and confusion as to which dollar is meant in articles. To make it as clear as possible, please specify.
• $123 — Although "$" is wikified to USD, it is hard to read
• 123$ — Although it is read aloud like this, this is not a standard way to write it. Dollars are sometimes written this way by Canadian francophones writing in English. This is also the way Portuguese escudos were expressed before the introduction of the euro.
• $123 (US) — non-standard

• £123 — This symbol does not only refer to the UK pound sterling. The use is thus ambiguous.
• ¥123 — similar to the above (ambiguity reasons)
• 50¢ — similar to the above (ambiguity reasons)
• CN元123 — this is bad since it mixes English and Chinese characters.
• CN123元 — same as above

See also

• see Wikipedia:Naming conventions (numbers and dates) for page naming specifics.