Spell out the number if the unit of measurement is written out and use a numeral when the unit of measurement is abbreviated.




Do not use points or plurals with abbreviated units of measurement. Also, insert a non-breaking space between the numeral and the unit so that these never become separated at line breaks. To do this in a Word document, first write the number and the unit all together (e.g., 2m, 6km) and then position your cursor between the number and the unit (2|m and 6|km) and press Control+Shift+Space. To do this in an HTML document, insert the entity   in that same position.