Formatting units of measurement
When specifying a unit of measurement, use a nonbreaking space between the number and the unit. This guidance applies to HTML and Markdown sources.
Not recommended: 64GB
However, when the unit of measure is money, degrees, or percent, don't leave a space.
In some contexts, it may be appropriate to indicate thousands of something by following a number with a lowercase "k". If you do that, then follow these guidelines:
- Don't put a space between the number and "k".
- Add a noun to indicate what the number measures, and to make clear that you're not using "k" as an abbreviation for "kilobytes."
Recommended: On this plan, you are limited to 55k download operations and 20k upload operations per day.
If you're writing about monetary amounts, make sure the reader knows what currency you're referring to. For example, the dollar sign—the $ symbol—can refer to US dollars, Canadian dollars, Mexican pesos, and several other currencies.
If there's any possibility of ambiguity, use a currency indicator before the amount. For details, see section 9.20 and following in the Chicago Manual of Style, 17th edition.