Numbers

These rules govern the use of numbers of all kinds, including times and dates.

The fundamental rule

Spell out whole-number words for one to ten; use figures for numbers above ten.

Some exceptions are acceptable on posters and other display materials, but only if there is no alternative.

How to write numbers

When discussing large numbers in text, do not use k/m/bn in the place of thousand/million billion. Instead write out the number either completely in words (for one to nine thousand/million/billion) or in a mixture of figures and words (for 10 thousand/million/billion and over).

47 Ronin lost almost $150 million at the box office.

"We get the warhead and we hold the world ransom for... one million dollars!"

If there are a lot of figures close to each other in a paragraph or text, some above nine and some below, use figures throughout to allow easy comparison by readers.

There were 3 patients to be seen and each needed 14 different tests run on them for 6 different diseases.

In body text spell out first for "first", "second" and so on up to and including "tenth"; use numbers and "st"/"nd"/"th" for larger ordinal numbers. The exception to this is in dates and times. Don't use superscript (to prevent problems with line spacing).

In headline text always use numbers as "st"/"nd"/"th".

I came second in the foot race last year, but this year I came 162nd.

My parcel arrived on 5 December.

Always use figures and symbols for percentages, measurements and currency. Use commas to punctuate numbers that include a ten thousands digit or more.

I can work 11% harder.

It is 1,000km to Turin from here.

You owe me £100,000.

Only ever use figures in tables or diagrams, never spelling out numbers in full. You can of course use other words normally.

Clown statistics
Average number of wigs	Long floppy shoes owned
1	35
2	22
3	8643

Times

Always use the 12-hour clock. Use a full stop between the hours and the minutes, not a colon.

We are going to meet for lunch at 1.30pm.

Don't use additional ".00" for times on the hour, and close up space between the number and the "am" or "pm".

The lecture starts at 4pm.

Use "noon" or "midnight" instead of "12", "12 noon" or "12 midnight".

All students must vacate the bouncy castle before midnight.

Dates

Always write dates in the format day month year. Use figures for dates even if they are ten or less.

The general election was held on Thursday 7 May 2015.

Don't use "th", "st" and "nd" with dates - just the number and the month - and never precede the number with "the".

The new semester begins Monday 12 January.

Include days of the week when writing dates unless doing so would be specifically confusing.

The lecture is scheduled for Tuesday 31 March.

Wednesday Adams will be giving a lecture on 31 March.

Spans of numbers and years

Shorten periods where it is not ambiguous to do so and use the shortest text possible. Always use at least two digits in the shortened version.

The Second World War (1939-45) was a turning point for Europe and the world.

A group of ardent protestors held the city hall 1973-76.

To refer to an academic or financial year, you should use the format "2011/12", separating the numbers with a slash.

Losses have been increasing for some time: we went further into debt in 2013/14 than we did in 2012/13.

If using "from" with a start date/time, always use "to" to indicate the end date/time rather than an en dash. Alternately, just use an en dash without "from".

The summer vacation runs from June to September.

The summer vacation runs June-September.

Return to The University of Nottingham Style Guide