A couple people have asked me recently about when to use figures for numbers (e.g. “25”) and when to spell them out (e.g. “six”).
One guideline is to spell out numbers one through nine and use figures for 10 or more. Another (the one I prefer) is to spell out numbers if they can be written as one or two words; otherwise, use figures. There are, however, exceptions to both rules:
- If a sentence begins with a number, either spell it out or rewrite the sentence with the number in a different position.
- Use figures for dates, addresses, percentages, fractions, decimals, scores, statistics, exact amounts of money, and the time.
Style guides disagree about whether you should maintain consistency within a sentence. Also, as Lunsford and Connors wisely note in The New St. Martin’s Handbook, “Conventions for expressing numbers vary from field to field, and you will want to make sure you understand the conventions of your own field—and follow them closely.”
- Capital Community College
- A Writer’s Reference, Fifth Edition, by Diana Hacker
- The New St. Martin’s Handbook by Andrea Lunsford and Robert Connors
- The Associated Press Stylebook