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{{hatnote|For currency conversion into US dollars, see [[Template:To USD]]}}
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{{Transwiki guide |small=yes |text=See [[Template:Convert/Transwiki guide|'''this information''']] on copying this template and modifying it for use on another wiki.}}
{{Lua|Module:Convert}}
'''Template {{tl|convert}}''' ''calculates'' from one measurement unit to another one, and then ''presents'' the results formatted. For example:
:<code><nowiki>{{convert|2|km|mi}}</nowiki></code> → {{convert|2|km|mi}} <small>(km entered, so converted into mile)</small>
:<code><nowiki>{{convert|7|mi|km}}</nowiki></code> → {{convert|7|mi|km}} <small>(mi entered, so converted into km)</small>

''Numbers'' can be rounded, ''units'' can be abbreviated into symbols:
:<code><nowiki>{{convert|2|km|mi|2|abbr=on}}</nowiki></code> → {{convert|2|km|mi|2|abbr=on}}
:<code><nowiki>{{convert|7|mi|km|2|abbr=on}}</nowiki></code> → {{convert|7|mi|km|2|abbr=on}}
Value ''ranges'' can be entered using <code>|to|...</code> or <code>|-|...</code>:
:<code><nowiki>{{convert|2|to|5|km|mi}}</nowiki></code> → {{convert|2|to|5|km|mi}}
:<code><nowiki>{{convert|2|-|5|km|mi}}</nowiki></code>  → {{convert|2|-|5|km|mi}}

Combined effect example:
:<code><nowiki>{{convert|2|-|5|km|mi|2|abbr=on}}</nowiki></code> → {{convert|2|-|5|km|mi|2|abbr=on}}
:<code><nowiki>{{convert|2|and|5|km|mi|sigfig=3|abbr=off}}</nowiki></code> → {{convert|2|and|5|km|mi|sigfig=3|abbr=off}}

{{hatnote|See [[Help:Convert]] for more detailed, technical information}}

==Units to convert==
Enter units to convert:
* <code><nowiki>{{convert|1|lb|kg}}</nowiki></code> → {{convert|1|lb|kg}}
:SI units generally accept prefixes, like "m" for micro (10<sup>&minus;3</sup>), and "M" for mega (10<sup>6</sup>)
:For "per" units, use "/" (slash): kg/ha
:For three-unit units etc.: see {{cl|Convert-like templates}}

==Unit name or symbol (abbreviation): ''1 pound'' or ''1 lb''?==
By default, the first quantity shows unit name, the second shows the symbol (or abbreviation):
* <code><nowiki>{{convert|1|lb|kg}}</nowiki></code> → {{convert|1|lb|kg}}

Using {{para|abbr|in}} is the ''reverse behaviour'' to the default:
*<code><nowiki>{{convert|1|lb|kg|abbr=in}}</nowiki></code> → {{convert|1|lb|kg|abbr=in}}

To abbreviate both or neither:
* <code><nowiki>{{convert|1|lb|kg|abbr=on}}</nowiki></code> → {{convert|1|lb|kg|abbr=on}} 
* <code><nowiki>{{convert|1|lb|kg|abbr=off}}</nowiki></code> → {{convert|1|lb|kg|abbr=off}}

When using scientific notation, the default is for the second (converted) quantity to be displayed using scientific notation:
* <code><nowiki>{{convert|100|e6mi|e6km}}</nowiki></code> → {{convert|100|e6mi|e6km}}

To display thousands, millions, etc., while abbreviating both input and output units use {{para|abbr|unit}}:
* <code><nowiki>{{convert|100|e6mi|e6km|abbr=unit}}</nowiki></code> → {{convert|100|e6mi|e6km|abbr=unit}}

===Convenience: {{tlf|cvt}} has {{para|abbr|on}} by default===
Template {{tl|cvt}} is the same as {{tlf|convert}}, except that it has {{para|abbr|on}} as the default behaviour. In {{tlf|cvt}}, all other options are available. So:
:<code><nowiki>{{cvt|1|lb|kg}}</nowiki></code> → {{cvt|1|lb|kg}}
is equivalent to:
:<code><nowiki>{{convert|1|lb|kg|abbr=on}}</nowiki></code> → {{cvt|1|lb|kg|abbr=on}}

==Adjective: ''a 10-mile distance''==
Use {{para|adj|on}} to produce the adjectival (hyphenated) form:
* <code><nowiki>A {{convert|10|mi|km|adj=on}} distance</nowiki></code> → A {{convert|10|mi|km|adj=on}} distance.
Default behaviour, for comparison:
* <code><nowiki>{{convert|10|mi|km}} to go</nowiki></code> → {{convert|10|mi|km}} to go.

Even with {{para|abbr|on}}, as per [[MOS:UNITSYMBOLS|MoS]] no hyphen is produced with unit symbols.

=={{anchor|Rounding}}Rounding: ''100 ft'' is ''30&nbsp;m'' or ''30.5&nbsp;m'' or ''30.48&nbsp;m''?==
By definition, 100&nbsp;ft equals {{convert|100|ft|m|sigfig=4|disp=out}}. In practical use, it is common to round the calculated metric number. With that, there are several possibilities.

===Default rounding===
By {{tlf|Convert}} default, the conversion result will be rounded either to precision comparable to that of the input value (the number of digits after the decimal point—or the negative of the number of non-significant zeroes before the point—is increased by one if the conversion is a multiplication by a number between 0.02 and 0.2, remains the same if the factor is between 0.2 and 2, is decreased by 1 if it is between 2 and 20, and so on) or to two significant figures, whichever is more precise. An exception to this is ''rounding temperatures'' (see [[#Rounding temperatures|below]]).

{| class="wikitable"
|-
! colspan="3" | Examples of rounding
|-
|'''Input'''||'''Displays as'''||'''Note'''
|-
|<code><nowiki>{{convert|123|ft|m|-1}}</nowiki></code> || {{convert|123|ft|m|-1}} ||
|-
|<code><nowiki>{{convert|123|ft|m}}</nowiki></code> || {{convert|123|ft|m}} || same output as with 0 (below)
|-
|<code><nowiki>{{convert|123|ft|m|0}}</nowiki></code> || {{convert|123|ft|m|0}} ||
|-
|<code><nowiki>{{convert|123|ft|m|1}}</nowiki></code> || {{convert|123|ft|m|1}} ||
|-
|<code><nowiki>{{convert|123|ft|m|2}}</nowiki></code> || {{convert|123|ft|m|2}} || exact value is 37.4904 m
|-
|<code><nowiki>{{convert|500|ft|m|-1}}</nowiki></code> || {{convert|500|ft|m|-1}} ||
|-
|<code><nowiki>{{convert|500|ft|m}}</nowiki></code> || {{convert|500|ft|m}} || same output as with -1 (above)
|-
|<code><nowiki>{{convert|500|ft|m|0}}</nowiki></code> || {{convert|500|ft|m|0}} || 
|-
|<code><nowiki>{{convert|500|ft|m|1}}</nowiki></code> || {{convert|500|ft|m|1}} ||
|-
|<code><nowiki>{{convert|500|ft|m|2}}</nowiki></code> || {{convert|500|ft|m|2}} || exact value is 152.4 m 
|-
|<code><nowiki>{{convert|500|ft|cm}}</nowiki></code> || {{convert|500|ft|cm}} || different output as with 0 (below)
|-
|<code><nowiki>{{convert|500|ft|cm|0}}</nowiki></code> || {{convert|500|ft|cm|0}} ||
|}<!--NOTE: rows require "nowiki", using &#123;{ disappears. -->

''Convert'' supports four types of rounding:

===Round to a given precision: ''use a precision number''===
Specify the desired precision with the ''fourth unnamed parameter'' (or third unnamed parameter if the "convert to" parameter is omitted; or fifth unnamed parameter if a range is specified; or fourth unnamed parameter again if a range is specified and the "convert to" parameter is omitted; needs to be replaced with a "precision" named parameter). The conversion is rounded off to the nearest multiple of {{frac|10}} to the power of this number. For instance, if the result is 8621 and the round number is "-2", the result will be 8600. If the result is "234.0283043" and the round number is "0", the result will be 234.

===Round to a given number of significant figures: ''{{para|sigfig|}}''===
To specify the output number to be with ''n'' significant figures use {{para|sigfig|&lt;number>}}:
* <code><nowiki>{{convert|1200|ft|m|sigfig=4}}</nowiki></code> → {{convert|1200|ft|m|sigfig=4}}
* <code><nowiki>{{convert|1200|ft|m|sigfig=3}}</nowiki></code> → {{convert|1200|ft|m|sigfig=3}}
* <code><nowiki>{{convert|1200|ft|m|sigfig=2}}</nowiki></code> → {{convert|1200|ft|m|sigfig=2}}
* <code><nowiki>{{convert|1200|ft|m|sigfig=1}}</nowiki></code> → {{convert|1200|ft|m|sigfig=1}}
Default behaviour, for comparison:
* <code><nowiki>{{convert|1200|ft|m}}</nowiki></code> → {{convert|1200|ft|m}}
Setting {{para|sigfig}} to a value less than 1 is meaningless:
* <code><nowiki>{{convert|1200|ft|m|sigfig=0}}</nowiki></code> → {{convert|1200|ft|m|sigfig=0}} {{nay}}

===Round to a multiple of 5: ''15'', ''20'', ''25'', ...===
Using {{para|round|5}} rounds the outcome to a multiple of 5.
* <code><nowiki>{{convert|10|m|ft}}</nowiki></code> → {{convert|10|m|ft}}
* <code><nowiki>{{convert|10|m|ft|round=5}}</nowiki></code> → {{convert|10|m|ft|round=5}}

Similar: using {{para|round|25}} rounds the outcome to a multiple of 25.
* <code><nowiki>{{convert|10|m|ft}}</nowiki></code> → {{convert|10|m|ft}}
* <code><nowiki>{{convert|10|m|ft|round=25}}</nowiki></code> → {{convert|10|m|ft|round=25}}
Default behaviour, for comparison:
* <code><nowiki>{{convert|10|m|ft|sigfig=4}}</nowiki></code> → {{convert|10|m|ft|sigfig=4}}

In a range, one can round ''each value'' individually to the default. Use {{para|round|each}}:
* <code><nowiki>{{convert|10 x 200 x 3000|m|ft}}</nowiki></code> → {{convert|10 x 200 x 3000|m|ft}}
* <code><nowiki>{{convert|10 x 200 x 3000|m|ft|round=each}}</nowiki></code> → {{convert|10 x 200 x 3000|m|ft|round=each}}

===<span id="Round to a multiple of a given fraction"></span>Round to a multiple of a given fraction: ''{{frac|2|3|16}} inch''===
Specify the desired ''denominator'' using {{para|frac|&lt;some positive integer&gt;}}. ([[Fraction (mathematics)|Denominator]] is the below-the-slash number, for example the 3 in {{frac|1|3}}).
* <code><nowiki>{{convert|5.56|cm|in|frac=16}}</nowiki></code> → {{convert|5.56|cm|in|frac=16}}
* <code><nowiki>{{convert|8|cm|in|frac=4}}</nowiki></code> → {{convert|8|cm|in|frac=4}}
The fraction is reduced when possible:
* <code><nowiki>{{convert|8|cm|in|frac=100}}</nowiki></code> → {{convert|8|cm|in|frac=100}}
Default behaviour uses decimal notation:
* <code><nowiki>{{convert|5.56|cm|in}}</nowiki></code> → {{convert|5.56|cm|in}}

==={{anchor|Rounding temperatures}}Rounding temperatures: ''°C'', ''°F'' and ''K''===
In temperatures, the conversion will be rounded either to precision comparable to that of the input value or to that which would give three significant figures when expressed in kelvins, whichever is more precise.

#{{#invoke:DemoTemplate|convert|10,000|C|F K}}
#{{#invoke:DemoTemplate|convert|10,000.1|C|F K}}
#{{#invoke:DemoTemplate|convert|-272|C|F K}}
#{{#invoke:DemoTemplate|convert|-272|C}}
#{{#invoke:DemoTemplate|convert|-300|C|F K}}
#{{#invoke:DemoTemplate|convert|0|C|F K}}

The precision of the input number in example (1) is one digit, but the precision of its Kelvins expression is three, so the precision of the Fahrenheit conversion is ''made'' three (made 180...) . (1) and (2) seem to belie the fact that a {{convert|0.1|C-change|F-change|disp=x| is a |abbr=off}}, and make the 32 degrees difference shown in (1) begin to seem off somehow.
Result (1) seems off until you set the [[significant figures]] yourself with {{para|sigfig}}:
:{{#invoke:DemoTemplate|convert|10000|C|sigfig=5}}
or you set the precision ''positionally'', relative to the decimal point (zero being ''at'' the decimal point):
:{{#invoke:DemoTemplate|convert|10000|C|0}}

The precision of the input number in example (2) is six, so the precision of the Fahrenheit output is, whereas before, Kelvins had determined it to be three. Examples (3) and (4) show how this can be hidden and generate questions, but it occurs there because the Kelvins conversion generated two fractional parts. (Before it was the input number that generated the fractional part.)  In example (3) the three input digits converted into five significant output digits because of the two digits after the decimal point, generated by the Kelvins conversion. This happened again in (5), but in (6) decimal fractions were neither given as input nor induced by the Kelvins conversion.

===Rounding input===
There is limited support for rounding the displayed ''input'' number.  The rounding tales place ''after'' conversion, so the output is based on the full-precision input.  This is useful when the input is produced by {{tlc|&#35;expr:}} or otherwise available to a higher precision than is usefully displayed, and it's desirable to avoid double-rounding.

To round the input to a specified number of digits after the decimal point, use one of the parameters:
* {{para|adj|ri0}}
* {{para|adj|ri1}}
* {{para|adj|ri2}}
* {{para|adj|ri3}}
Note that there is no {{para|adj|ri-1}}{{nay}} or similar for rounding above the decimal place.  Neither is there support for significant figures, multiples of 5, or any other output-rounding feature.

The default precision is computed based on the input, so an explicit output precision must usually be supplied:
* {{tlc|convert|4.14159|mi|km|adj{{=}}ri0}} → {{convert|4.14159|mi|km|adj=ri0}} {{nay}} (precisions are mismatched)
* {{tlc|convert|4.14159|mi|km|0|adj{{=}}ri0}} → {{convert|4.14159|mi|km|0|adj=ri0}} {{aye}}

In this case, if the input were rounded before conversion, a different result would be obtained:
* {{tlc|convert|<nowiki>{{#expr:4.14159 round 0}}</nowiki>|mi|km|0}} → {{convert|{{#expr:4.14159 round 0}}|mi|km|0}} {{nay}} (double rounding)

==Into multiple units: ''{{convert|10|C|F K}}''==
Separate the multiple output units by a space:
* <code><nowiki>{{convert|10|C|F K}}</nowiki></code> → {{convert|10|C|F K}}
* <code><nowiki>{{convert|5|km|mi nmi}}</nowiki></code> → {{convert|5|km|mi nmi}}
If the output unit names contain spaces, use <code>+</code> as the separator.

See also:
* For multiple-unit options like ''1 ft 5 in'', see {{section link||In input}} and {{section link||In output}}.

==Ranges of values==
{{For|a conversion of a difference|#Units of difference}}
A ''range'' converts ''two'' values and separates them by your choice of words and punctuation.

===A range: ''6 to 17 kg (13 to 37 lb)''===
Range indicators are entered as the second parameter (between the values). Range separators can be:<br/>
{{Convert/doc/range separator list}}

===Multiple dimensions: ''{{convert|6|x|12|m|ft|abbr=on}}''===
Use <code>by</code>:
* <code><nowiki>{{convert|6|by|12|ft|m}}</nowiki></code> → {{convert|6|by|12|ft|m}}

Use <code>×</code>, multiplication sign, or <code>x</code>, letter:
* <code><nowiki>{{convert|6|x|12|m|ft}}</nowiki></code> → {{convert|6|x|12|m|ft}}

In science, the formal way is to set <code>&#x7c;x&#x7c;</code> and {{para|abbr|on}} (keeping dimensions right, like in ''area = x km<sup>2</sup>''):
* <code><nowiki>{{convert|6|x|12|m|ft|abbr=on}}</nowiki></code> → {{convert|6|x|12|m|ft|abbr=on}}

===About ''feet, inch'' in ranges and multiples===
While it is possible to enter feet, inch in a simple conversion, this is not possible for ranges:
* <code><nowiki>{{convert|1|ft|3|in|x|3|ft|5|in|mm}}</nowiki></code> → {{convert|1|ft|3|in|x|3|ft|5|in|mm}} {{nay}}
Default behaviour, for comparison:
* <code><nowiki>{{convert|1|ft|3|in|mm}}</nowiki></code> → {{convert|1|ft|3|in|mm}}

==Words==
===Spelling of unit name: UK ''metre'' or US ''meter''?===
Default spelling of units is en-UK. To show en-US spelling, use {{para|sp|us}}:
:<code><nowiki>{{convert|1|m|ft}}</nowiki></code> → {{convert|1|m|ft}}—''default''
:<code><nowiki>{{convert|1|m|ft|sp=us}}</nowiki></code> → {{convert|1|m|ft|sp=us}}

===Spell out numbers: ''ten miles''===
To write a number in words, use {{para|spell|in}}:
* <code><nowiki>{{convert|10|mi|m|spell=in}}</nowiki></code> → {{convert|10|mi|m|spell=in}}

To spell out both in and out values, use {{para|spell|on}}:
* <code><nowiki>{{convert|10|mi|m|spell=on}}</nowiki></code> → {{convert|10|mi|m|spell=on}}

To make first letter a capital, use {{para|spell|In}}, {{para|spell|On}}
* <code><nowiki>{{convert|10|mi|m|spell=In}}</nowiki></code> → {{convert|10|mi|m|spell=In}}
* <code><nowiki>{{convert|10|mi|m|spell=On}}</nowiki></code> → {{convert|10|mi|m|spell=On}}

Remember that the spelling of the units (ft, m) is independently set by {{para|abbr|}}. To the extreme:
* <code><nowiki>{{convert|10|mi|m|spell=on|abbr=off|sp=us}}</nowiki></code> → {{convert|10|mi|m|spell=on|abbr=off|sp=us}}

===Inserted before units: ''4 planted acres''===
*<code><nowiki>{{convert|4|acre||adj=pre|planted}}</nowiki></code> → {{convert|4|acre||adj=pre|planted}}
<code>disp=preunit</code> is similar, but has no separator after the specified text, and can have different text for the output value:
*<code><nowiki>{{convert|4|acre||disp=preunit|planted }}</nowiki></code> → {{convert|4|acre||disp=preunit|planted }}
*<code><nowiki>{{convert|4|acre||disp=preunit|planted |reforested-}}</nowiki></code> → {{convert|4|acre||disp=preunit|planted |reforested-}}

===After adjective unit: ''A {{convert|10|ft|ft|adj=mid|-long|disp=out|order=flip}} corridor''===
:<code><nowiki>{{convert|10|ft|m|adj=mid|-long}}</nowiki></code> → {{convert|10|ft|m|adj=mid|-long}}

===Plurals: ''1&nbsp;inch, 2&nbsp;inches''===
The unit symbol is singular always. Depending on the preceding number only, a unit name can be shown plural.
* <code><nowiki>{{convert|1|metre}}</nowiki></code> → {{convert|1|metre}}
* <code><nowiki>{{convert|2|metre}}</nowiki></code> → {{convert|2|metre}}
* <code><nowiki>{{convert|2|metre|abbr=on}}</nowiki></code> → {{convert|2|metre|abbr=on}}

;Exception:
Entering the unit spelled <code>|foot|</code> forces singular output "foot", whatever the number is.
* <code><nowiki>{{convert|100|foot|abbr=off}}</nowiki></code> → {{convert|100|foot|abbr=off}}

===Fractions: ''one-eighth of an imperial pint''===
The convert template also supports spelling out fractions.
* <code><nowiki>{{convert|3+1/2|oz|g|spell=in}}</nowiki></code> → {{convert|3+1/2|oz|g|spell=in}}
Any additional words needed for the fraction can also be added at the end of the template.
* <code><nowiki>{{convert|1/8|imppt|mL|spell=in|adj=pre|of an}}</nowiki></code> → {{convert|1/8|imppt|mL|spell=in|adj=pre|of an}}
<!-- todo: decimals & negative examples -->

===Wrapping and line breaking===
:See {{section link|Help:Convert|Wrapping and line breaking}}

==Numbers==

===Using an SI prefix: ''gigameter (Gm)'', or ''micrometer (&#x03BC;m)''===
{{Sidebar metric prefixes (small)}}
Units can have an [[metric prefix|SI prefix]] like <code>G</code> before the unit: <code>Gm</code>, and <code>giga</code> before the name: <code>gigameter</code>. These are plain multiplication factors.

To illustrate, these are trivial calculations (from meter to meter), showing the multiplication factor:
* {{convert|12|Gm|m|abbr=on}}
* {{convert|12|μm|m|abbr=on}}

The prefix can be added before the SI unit (here: unit <code>m</code> for meter):
* <code><nowiki>{{convert|12|Gm|mi|abbr=on}}</nowiki></code> → {{convert|12|Gm|mi|abbr=on}}
* <code>Mm</code>: {{convert|12|Mm|mi|abbr=on}}
* <code>km</code>: {{convert|12|km|ft|abbr=on}}
* <code>mm</code>: {{convert|12|mm|in|abbr=on}}
* <code>&#x03BC;m</code>: {{convert|12|μm|mm|abbr=on}}
* <code>um</code>: {{convert|12|um|mm|abbr=on}} (letter "u" can be used for "&#x03BC;" here)

The prefix can be used in the output unit:
* <code><nowiki>{{convert|12000|mi|Mm|abbr=on}}</nowiki></code> → {{convert|12000|mi|Mm|abbr=on}}
* <code><nowiki>{{convert|12|in|μm|abbr=on}}</nowiki></code> → {{convert|12|in|μm|abbr=on}}

As an exception, the non-SI unit "inch" can have the "&#x03BC;" prefix too)
* <code><nowiki>{{convert|12|&#x03BC;m|μin|abbr=on}}</nowiki></code> → {{convert|12|μm|μin|abbr=on}}

{{further information|Help:Convert units#SI prefixes}}

===Engineering notation: ''7 × 10<sup>6</sup> m''===

====In the unit: ''e6m''====
[[Engineering notation|Engineering number notations]] like ''7{{smallcaps|E}}6'' (for 7 × 10<sup>6</sup>) can be entered as a "prefix" to the unit:
* <code><nowiki>{{convert|7|e6m}}</nowiki></code> → {{convert|7|e6m}}

The same is possible for the output unit:
* <code><nowiki>{{convert|23,000,000|ft|e6m}}</nowiki></code> → {{convert|23,000,000|ft|e6m}}

Any standard unit (not a combination, multiple, or built-in unit) can have such a prefix:
* <code>e3</code> (thousand),
* <code>e6</code> (million),
* <code>e9</code> (billion),
* <code>e12</code> (trillion),
* <code>e15</code> (quadrillion).

===Scientific notation: ''1.23 × 10<sup>−14</sup>''===
In [[scientific notation]], a number is written like {{rnd|12.3e-15|16}}. The plain number has exactly one digit before the decimal point.

With {{tlf|convert}}, the input can be in e-notation such as <code>12.3e4</code>. This value is displayed as a power of ten, and the output is displayed in scientific notation, except that an output value satisfying 0.01 <= v < 1000 is shown as a normal number. In addition, if the output value is 1000 and sigfig=4 is used, the value is displayed as a normal number.
*<code><nowiki>{{convert|12.3e-15|atm|atm|abbr=on}}</nowiki></code> → {{convert|12.3e-15|atm|atm|abbr=on}}
*<code><nowiki>{{convert|0.00000005|atm|atm|abbr=on}}</nowiki></code> → {{convert|0.00000005|atm|atm|abbr=on}}

===Input with fractions: ''{{convert|1+1/2|in|mm|1}}''===
The number to convert can be written in fractions. Both <code>/</code> (keyboard slash) and <code>⁄</code> (fraction slash) are accepted:
*<code><nowiki>{{convert|1/2|in|mm|1}}</nowiki></code> → {{convert|1/2|in|mm|1}}
*<code><nowiki>{{convert|1⁄2|in|mm|1}}</nowiki></code> → {{convert|1⁄2|in|mm|1}}

With integers, use a <code>+</code> sign
*<code><nowiki>{{convert|2+1⁄2|in|mm|1}}</nowiki></code> → {{convert|2+1⁄2|in|mm|1}}

When negative, use a hyphen <code>-</code> and repeat it:
*<code><nowiki>{{convert|-2-1⁄2|in|mm|1}}</nowiki></code> → {{convert|-2-1⁄2|in|mm|1}}
*<code><nowiki>{{convert|2-1⁄2|in|mm|1}}</nowiki></code> → {{convert|2-1⁄2|in|mm|1}} Note: this is read as a range
*<code><nowiki>{{convert|-2+1⁄2|in|mm|1}}</nowiki></code> → {{convert|-2+1⁄2|in|mm|1}} {{nay}} Should be a number, not an expression (do not require a calculation)

===Output with horizontal fraction bar in: ''{{sfrac|1|2}}&nbsp;inch''===
<!-- technical restriction: TOC does not show the example horizontal bar intended here; rephrased section title-->
Using a double slash (<code>//</code>) returns a horizontal bar fraction:
* <code><nowiki>{{convert|1//2|in|mm|1}}</nowiki></code> → {{convert|1//2|in|mm|1}}
* <code><nowiki>{{convert|2+1//2|in|mm|1}}</nowiki></code> → {{convert|2+1//2|in|mm|1}}

===Thousands separator: ''1,000 mi'' or ''1000 mi''===
In input, a comma for thousands separator is accepted but not required; a gap (space) is not accepted. In output, by default, the thousand separator is the comma:
* <code><nowiki>{{convert|1234567|m|ft}}</nowiki></code> → {{convert|1234567|m|ft}}
* <code><nowiki>{{convert|1,234,567|m|ft}}</nowiki></code> → {{convert|1,234,567|m|ft}}
* <code><nowiki>{{convert|1 234 567|m|ft}}</nowiki></code> → {{convert|1 234 567|m|ft}} {{nay}}

Set {{para|comma|off}} to remove the separator from the output:
* <code><nowiki>{{convert|1234567|m|ft|comma=off}}</nowiki></code> → {{convert|1234567|m|ft|comma=off}}

Use {{para|comma|gaps}} to use digit grouping by gap (thin space) as a thousands separator:
* <code><nowiki>{{convert|1234567|m|ft|comma=gaps}}</nowiki></code> → {{convert|1234567|m|ft|comma=gaps}}
Default behaviour, for comparison:
* <code><nowiki>{{convert|1234567|m|ft}}</nowiki></code> → {{convert|1234567|m|ft}}

Setting {{para|comma|5}} will only add the separator when the number of digits is 5 or more:
* <code><nowiki>{{convert|1234|m|ft|comma=5}}</nowiki></code> → {{convert|1234|m|ft|comma=5}}
* <code><nowiki>{{convert|1234567|m|ft|comma=5}}</nowiki></code> → {{convert|1234567|m|ft|comma=5}}
Default behaviour, for comparison:
* <code><nowiki>{{convert|1234|m|ft}}</nowiki></code> → {{convert|1234|m|ft}}

==Output manipulation==
===Brackets and separators: ''10 m [33 ft]''===
Punctuation that distinguishes the two measurements is set by {{para|disp|}}.<br/>
Options are: <code>b</code> <small>(the default)</small>, <code>sqbr</code>, <code>comma</code>, <code>or</code>, <code>br</code>, <code>x{{!}}…</code>:
* <code><nowiki>{{convert|10|m|ft|disp=sqbr}}</nowiki></code> → {{convert|10|m|ft|disp=sqbr}}
* <code><nowiki>{{convert|10|m|ft|disp=comma}}</nowiki></code> → {{convert|10|m|ft|disp=comma}}
* <code><nowiki>{{convert|10|m|ft|disp=or}}</nowiki></code> → {{convert|10|m|ft|disp=or}}
Default behaviour, for comparison:
* <code><nowiki>{{convert|10|m|ft}}</nowiki></code> → {{convert|10|m|ft}}

Setting {{para|disp|br}} will force a new line (<code>&lt;br/></code>)
* <code><nowiki>{{convert|10|m|ft|disp=br}}</nowiki></code> → {{convert|10|m|ft|disp=br}}

Also {{para|disp|br()}} will force a new line, and keep the brackets (useful in tables):
* <code><nowiki>{{convert|10|m|ft|disp=br()}}</nowiki></code> → {{convert|10|m|ft|disp=br()}}

Setting {{para|disp|x{{!}}…}} allows any text as separator:
* <code><nowiki>{{convert|10|m|ft|disp=x|_MyText_}}</nowiki></code> → {{convert|10|m|ft|disp=x|_MyText_}} <small>(To display spaces, use <code>&amp;nbsp;</code>)</small>
<!--todo: works for multiple freetexts too! |disp=x|TextA|TextB -->

===Flipping (reordering) the two measurements: ''{{convert|1|mi|m|order=flip|sigfig=5|abbr=off}}'' ===
Setting {{para|order|flip}} will flip (swap) the two measurements:
* <code><nowiki>{{convert|1|mi|m|order=flip}}</nowiki></code> → {{convert|1|mi|m|order=flip|sigfig=5|abbr=off}}<!-- Extra settings added to enhance the illustration. Don't know if this is ideal way of documenting. DePiep, August 2014. --></small>
Default behaviour, for comparison:
* <code><nowiki>{{convert|1|mi|m}}</nowiki></code> → {{convert|1|mi|m|sigfig=5|abbr=off}}

When converting to multiple units, the effect is:
* <code><nowiki>{{convert|10|km|mi nmi|order=flip}}</nowiki></code> → {{convert|10|km|mi nmi|order=flip|sigfig=5|abbr=off}}
* <code><nowiki>{{convert|10|km|nmi mi|order=flip}}</nowiki></code> → {{convert|10|km|nmi mi|order=flip|sigfig=5|abbr=off}}

=== Displaying parts of the result: ''{{convert|2|cuyd|m3|abbr=values}}''===
It is possible to display only parts of the conversion result:
<!-- todo: describe effect of order=flip ("out" means 1st or 2nd measurement?) -->

{| class="wikitable"
! Convert !! Output !! Description
|-
| <code><nowiki>{{convert|2|cuyd|m3}}</nowiki></code> || {{convert|2|cuyd|m3}}
| Default behaviour, for comparison
|-
| <code><nowiki>{{convert|2|cuyd|m3|abbr=values}}</nowiki></code>
| {{convert|2|cuyd|m3|abbr=values}} || Input and output numbers
|-
| <code><nowiki>{{convert|2|cuyd|m3|disp=unit}}</nowiki></code> || {{convert|2|cuyd|m3|disp=unit}}
| Input unit
|-
| <code><nowiki>{{convert|2|cuyd|m3|disp=unit|adj=on}}</nowiki></code> || {{convert|2|cuyd|m3|disp=unit|adj=on}}
| Input unit, adjective (hyphenated)
|-
| <code><nowiki>{{convert|2|cuyd|cuyd|disp=out}}</nowiki></code> || {{convert|2|cuyd|cuyd|disp=out}} || Input (''workaround''. {{nowrap|1=Note repetition of unit in input}})
|-
| <code><nowiki>{{convert|2|cuyd|m3|abbr=~}}</nowiki></code> || {{convert|2|cuyd|m3|abbr=~}}
| Input: both name and symbol
|-
| <code><nowiki>{{convert|2|cuyd|m3|disp=unit2}}</nowiki></code> || {{convert|2|cuyd|m3|disp=unit2}} || Output unit (symbol)
|-
| <code><nowiki>{{convert|2|cuyd|m3|disp=unit2|abbr=off}}</nowiki></code> || {{convert|2|cuyd|m3|disp=unit2|abbr=off}} || Output unit (name)
|-
| <code><nowiki>{{convert|2|cuyd|m3|disp=number}}</nowiki></code> || {{convert|2|cuyd|m3|disp=number}}
| Output value
|-
| <code><nowiki>{{convert|2|cuyd|m3|disp=out}}</nowiki></code> || {{convert|2|cuyd|m3|disp=out}}
| Output value and unit
|-
| <code><nowiki>{{convert|2|cuyd|m3|disp=out|abbr=off}}</nowiki></code> || {{convert|2|cuyd|m3|disp=out|abbr=off}}
| Output value and unit
|}

===Display both input name and symbol: ''2 kilopascals [kPa]''===
Setting {{para|abbr|~}} returns both name and  symbol of the first (input) unit:
* <code><nowiki>{{convert|2|kPa|psi|abbr=~}}</nowiki></code> → {{convert|2|kPa|psi|abbr=~}}
* <code><nowiki>A {{convert|2|kPa|psi|abbr=~|adj=on}} pressure</nowiki></code> → {{nowrap|A {{convert|2|kPa|psi|abbr=~|adj=on}} pressure}}

==Table options==
For the [[Help:Table/Manual tables|wikitable]] structure, there are three options: add a line-break, split the result over columns and make the table sortable.

===Enforced line break===
{{para|disp|br}} adds a line-break and omits brackets.

{{para|disp|br()}} adds a line-break and does add brackets to the converted value. This may be useful in tables:
{| class=wikitable
! {{para|disp|br}} !! {{para|disp|br()}}
|-
|{{convert|100|km|mi|disp=br}}
|{{convert|100|km|mi|disp=br()}}
|}

===Table columns showing numbers only===
Using {convert} in a table cell, with {{para|disp|table}} splits the result over two columns:
:<code><nowiki>{{convert|10|m|ft|disp=table}}</nowiki></code> →
::<code>{{convert|10|m|ft|disp=table}}</code>

{{para|disp|tablecen}} does the same, and also centers the text:
:<code><nowiki>{{convert|20|m|ft|disp=tablecen}}</nowiki></code> → 
::<code>{{convert|20|m|ft|disp=tablecen}}</code>

The units are added as a column header:
:{| class=wikitable
! style="width:10em;" | &nbsp;
! style="width:10em;" | m
! style="width:10em;" | ft
|-
| {{para|disp|table}}
| {{convert|10|m|ft|disp=table}}
|-
|{{para|disp|tablecen}}
| {{convert|20|m|ft|disp=tablecen}}
|-
|{{para|disp|&lt;other>}} <small>(default)</small>
|{{convert|30|m|ft|disp=}}
|}

===Sorting===
Use {{para|sortable|on}} to include a ''hidden numerical sortkey'' in the output, suitable for use in a [[Help:Sorting|table with sortable columns]]. Technically, this places a hidden string before the actual displayed values:
:<code><nowiki>{{convert|10|m|ft|sortable=on}}</nowiki></code> {{nowrap|1=→ &lt;span style="display:none">}}7001100000000000000<wbr />&lt;/span>10 metres (33&amp;nbsp;ft)

Use both {{para|disp|table}} and {{para|sortable|on}} together to produce table columns (pipe symbols) for each value in sortable columns:

:{| class="wikitable sortable"
!
! m
! ft
|-
| A
| {{convert|15+3/4|m|ft|disp=table|sortable=on}}
|-
| B
| {{convert|15.5|m|ft|disp=table|sortable=on}}
|-
| C
| {{convert|16.0|m|ft|disp=table|sortable=on}}
|-
| D
| {{convert|16|m|ft|disp=table|sortable=on}}
|}

The generated sortkey is calculated in a consistent way based on both the value and its unit as passed to the convert template. In most cases convert uses the passed value converted to SI base units. It is therefore not necessarily the displayed value or other alternate units and is calculated regardless of output format options. Using different units or different order of units in individual rows should therefore not lead to incorrect sorting, although variations in rounding can give surprising results, since an unrounded number is used for the sortkey.

==Units==
===All units===
{{selfref|See also: [[Template:Convert/list of units|Convert/list of units]]}}
{{hatnote|Units are case-sensitive: use {{xt|kW}}, not {{!xt|KW}} or {{!xt|kw}}}}
<div style="height: 400px; overflow: auto; padding: 3px; border: 1px solid #aaa;">
{{Convert/list of units}}
</div>

==='per' units: ''kg/hl''===
When using a slash (<code>/</code>), a unit like <code>kg/hl</code> is recognized as kilograms ''per'' hectolitre and will be converted with other mass/volume units.
* <code><nowiki>{{convert|1000|kg/hl}}</nowiki></code> → {{convert|1000|kg/hl}}

==={{anchor|Units of difference}}Units of difference: Expressing a change or difference in temperature===
We have already discussed standard temperature conversions (°C, °F, K), as shown in these two examples:
* {{#invoke:DemoTemplate|convert|10|C}} (standard temperature conversion)
* {{#invoke:DemoTemplate|convert|10-15|C}} (standard temperature range conversion)

When expressing a temperature ''change'' (e.g., "The temperature ''increased'' by 10&nbsp;°C"), or when ''comparing'' temperatures (e.g., "10 to 15&nbsp;°C ''warmer''"), we cannot use the standard temperature units ({{para||C}}, {{para||F}} and {{para||K}}). Instead, we must use one of the following "units of difference": {{para||C-change}}, {{para||F-change}} and {{para||K-change}}. 

Compare the following two examples with the two above:

* {{#invoke:DemoTemplate|convert|10|C-change}} increase in temperature
* {{#invoke:DemoTemplate|convert|10-15|C-change}} warmer than normal

To produce multiple units in the output:
* {{#invoke:DemoTemplate|convert|10|C-change|F-change K-change}} difference

===Multiple units: ''1 ft 5 in''===
====In input====
Base document {{slink|Module:Convert/documentation/conversion data/doc|Input multiples|nopage=y}} lists options for ''multiple unit input'' (like <code>ft,in</code>). It can catch predefined sets only (units that can be subdivided; e.g., yd into ft):
* <code><nowiki>{{convert|1|yd|2|ft|3|in}}</nowiki></code> → {{convert|1|yd|2|ft|3|in}}
* <code><nowiki>{{convert|2|ft|3|in|cm}}</nowiki></code> → {{convert|2|ft|3|in|cm}}
* <code><nowiki>{{convert|1|lb|5|oz|g}}</nowiki></code> → {{convert|1|lb|5|oz|g}}

====In output====
Available multiple-unit output options predefined, like <code>ftin</code> and <code>ydftin</code>. The full list is at {{slink|Module:Convert/documentation/conversion data/doc|Output multiples|nopage=y}}.
* <code><nowiki>{{convert|2|m|ftin}}</nowiki></code> → {{convert|2|m|ftin}}
* <code><nowiki>{{convert|2|m|ft in}}</nowiki></code> → {{convert|2|m|ft in}}, using a space, returns the decimal point
Default behaviour, for comparison:
* <code><nowiki>{{convert|2|m}}</nowiki></code> → {{convert|2|m}}

See also:
* {{tl|hands}} a length used to measure horses
* {{tl|Long ton}} a weight in ton, cwt, qr and lb
<!-- todo: mention the 0-3 limits -->

===Currency per unit: ''$/mi &rarr; $/km''===
Using currency symbols in a ''$ per unit'' value, you can convert the per-unit:
* <code><nowiki>{{convert|10|$/mi|$/km}}</nowiki></code> → {{convert|10|$/mi|$/km}}

You can set the currency in ''both'' values using {{para|$|€}}:
* <code><nowiki>{{convert|10|$/mi|$/km|$=€}}</nowiki></code> → {{convert|10|$/mi|$/km|$=€}}

It is ''not'' possible to convert the currency. So, this result (mixed currencies) is ''not'' possible: {{!mxt|1=$15 per mile (€8.6/km)}} {{nay}}

==Using convert inside templates==
For usage in template code, like infoboxes, {{tlf|Convert}} has these options:
;Pre-formatting fraction input
* [[Module:Convert/helper]] can read regular input and pre-format it into {{tlf|Convert}}-accepted input.
:Your template can accept {{para|input|16 7/8}} and use <nowiki>{{#invoke:Convert/helper|number|16 7/8}}</nowiki> &rarr; {{#invoke:Convert/helper|number|16 7/8}}

;Using a Wikidata property
* Adding the Wikidata property code, like code {{para|input|P2073}}, to your template code automatically returns the Wikidata property for that article, and convert it. Both number and unit are read.
Note: to return that property value for an ''other'' article, use {{para|qid}}. 

Example for {{Wikidata property link|P2073}}:
Note: this example uses {{para|qid|Q1056131}} (testing for {{Wikidata entity link|Q1056131}})
* <code><nowiki>{{convert|input=P2073|qid=Q1056131|ftin|abbr=on}}</nowiki></code>  &rarr; {{convert|input=P2073|qid=Q1056131|ftin|abbr=on}}
* <code><nowiki>{{convert|input=P2073|qid=Q1056131|km|abbr=on}}</nowiki></code>  &rarr; {{convert|input=P2073|qid=Q1056131|km|abbr=on}}
* <code><nowiki>{{convert|input=P2073|qid=Q1056131|km|abbr=on|disp=out}}</nowiki></code>  &rarr; {{convert|input=P2073|qid=Q1056131|km|abbr=on|disp=out}}
:For example see [[template:Infobox Telescope]].

==Parameter list==
{{convert/doc/parameter list}}

==Deprecated options==
{{Convert/doc/deprecations list}}

==TemplateData==
{{TemplateDataHeader}}

<templatedata>
{
	"description": "Converts measurements to other units.",
	"params": {
		"1": {
			"label": "value",
			"description": "the value to convert",
			"type": "number",
			"required": true
		},
		"2": {
			"label": "from unit",
			"description": "the unit for the provided 'value'",
			"type": "string/line",
			"example": "km",
			"required": true
		},
		"3": {
			"label": "to units",
			"description": "the unit to convert into",
			"type": "string",
			"example": "mi",
			"suggested": true
		},
		"4": {
			"label": "precision or suffix",
			"description": "significant digits after decimal dot or, if negative, exponent of ten",
			"type": "number"
		},
		"lk": {
			"label": "link units",
			"description": "“on” all, “in” input, “out” output or “off” no units",
			"default": "off",
			"type": "string",
			"example": "on"
		},
		"abbr": {
			"label": "abbreviation",
			"description": "display for the units: “on” unit symbols, “off” all unit names in full words, “in” input unit symbol, “out” abbreviated output units, “unit” both input and output units abbreviated when using scientific notation, “values” no units at all",
			"default": "out",
			"type": "string"
		},
		"sp": {
			"label": "spelling",
			"description": "“us” display U.S. spelling of unit names",
			"type": "string",
			"example": "us"
		},
		"adj": {
			"label": "adjective",
			"description": "adjectival form (singular unit name appended by hyphen) “on” or “mid” to put conversion at end",
			"type": "boolean",
			"example": "on",
			"default": "off"
		},
		"disp": {
			"label": "conversion",
			"description": "display conversion result: “or” after ‘or’, “x” with custom prefix and suffix, “b” in parentheses, “table”/“tablecen”, “output only” alone, “output number only” alone and without unit, “unit” not at all but input unit; if the value is a number it is used as precision",
			"type": "string",
			"example": "b"
		},
		"order": {
			"label": "ordering",
			"description": "“flip” returns converted value first, input value second.",
			"type": "string",
			"example": "flip"
		},
		"sigfig": {
			"label": "significant figures",
			"description": "number that sets the number of significant figures",
			"type": "number"
		},
		"round": {
			"label": "rounding output",
			"description": "“5” rounds the output number to nearest multiple of 5, “25” to nearest multiple of 25, “each” rounds each number in a range",
			"type": "number"
		},
		"comma": {
			"label": "thousands separator",
			"description": "Sets or suppresses thousand separator in the numbers. “off” = no separator; “gaps”: use space not comma; “5” and “gaps5”: only add separator when number > 5 positions (10,000 or more)",
			"default": "on",
			"type": "string",
			"example": "off"
		},
		"sortable": {
			"label": "sort key",
			"description": "“on” generates a hidden sort key",
			"type": "string",
			"example": "on"
		},
		"spell": {}
	},
	"format": "inline"
}
</templatedata>
<!--''to be added''
==Glossary==
;unit code
:
;unit symbol
:
-->

==See also==
* {{Temp|Cvt}}
* {{Temp|SI units}}
{{Convert navs}}
<noinclude>
[[Category:Convert by module documentation| ]]
</noinclude><includeonly>{{#ifeq:{{SUBPAGENAME}}|doc||
[[Category:Convert templates| ]]
[[Category:Conversion templates]]
[[Category:Numbers as words conversion templates]]
[[Category:Sorting templates]]
}}</includeonly>