1–9—write out one, nine, (i.e. single-digit numbers); from then on the number 10, 11 etc.
If a mix of related numbers above and below nine appears in one sentence, use figures:
- Unbelievably, only 2 of the 110 people on the train were injured.
Always start a sentence with a word:
- Two out of 110 people were injured.
For dollars, you can use just the $ symbol if it’s clear that it represents the local currency, but identify all other types of dollar (e.g. CAN$). When using the code and symbol, do not leave a space between the unit and quantity (e.g. US$500).
Examples of currency formats are listed below. You can also refer to the official ISO-4217 website for currency codes for all other countries.
|United States||US dollar||US$||USD|
When a number is associated with a unit of measurement, it is normally given as a digit, for example 5 volts, 3 MB. Leave a space between the figure and unit of measurement. However, the money symbol and percent symbol are always closed up. (If a currency code is used rather than a money symbol, leave a space between it and the figure.)
- 10 MB, 20 kg, $24, 10%, USD 342 million
Abbreviated units of measurements have no full stop and take no s in the plural.
- 10 MB, not 10 MBs
With abbreviations, capitalisation is important, for example Mb means megabits, but MB means megabytes.
Never allow the unit and amount to be separated over a new line.
Time of day
Generally, spell out even, half and quarter hours:
- The meeting continued until half past three.
- I’ll be there by ten o’clock.
Use figures for when you want to emphasise the exact time:
- 6.20 a.m. (Note that in American English a colon is used between hour and minute.)
When a 24-hour clock is required, use the following style:
- 04:00; 12:00; 15:53