Editing Template:Convert/doc (section)

==Words==
===Spelling of unit name: international ''metre'' or US ''meter''?===
Default spelling of units is in the en (generic) locale. 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}}

===<span id="spell"></span>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 the 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}}

===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''===
Note that two units (in this case, ft and m) are required. Use with just one unit will generate an error message.
:<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 "foot" instead of "ft" 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}}

===<span id="million"></span>Spelling out "thousands", "millions", etc.===
Most unit codes accept a prefix of e3 (thousand) or e6 (million) or e9 (billion).
* <code><nowiki>{{convert|100|e6mi|e6km}}</nowiki></code> → {{convert|100|e6mi|e6km}}
* <code><nowiki>{{convert|120|e6acre}}</nowiki></code> → {{convert|120|e6acre}}
* <code><nowiki>{{convert|120|e6acre|e3km2}}</nowiki></code> → {{convert|120|e6acre|e3km2}}

To display both input and output in scientific notation, use {{para|abbr|on}}
* <code><nowiki>{{convert|100|e6mi|e6km|abbr=on}}</nowiki></code> → {{convert|100|e6mi|e6km|abbr=on}}

To spell out "thousands", "millions", etc., {{para|abbr|unit}} abbreviates the unit; {{para|abbr|off}} displays both full unit names.
* <code><nowiki>{{convert|100|e6mi|e6km|abbr=unit}}</nowiki></code> → {{convert|100|e6mi|e6km|abbr=unit}}
* <code><nowiki>{{convert|100|e6mi|e6km|abbr=off}}</nowiki></code> → {{convert|100|e6mi|e6km|abbr=off}}