Writing numbers can be confusing. Time and again, I comes across people who don’t know when they should write out a number (like four) or whether they should use figures (like 26). What doesn’t help is that the main style guides don’t agree.
For example, MLA (8th edition, p. 92) recommends spelling numbers when they can be written in 1 or 2 words:
In discussions that require few numbers, you may spell out numbers written in a word or two and represent other numbers by numerals.
APA (6th edition, p. 111), on the other hand, suggests using numerals for anything above 10 (among other instances):
Use numerals to express
- numbers 10 and above
- numbers in the abstract of a paper . . .
- numbers that immediately precede a unit of measurement
- numbers that represent statistical or mathematical functions, fractional or decimal quantities, percentages, ratios, and percentiles an quartiles
- numbers that represent time, dates, ages, scores and points on a scale, exact sums of money, and numerals as numerals
- numbers that denote a specific place in a numbered series, parts of books and tables, and each number in a list of four or more numbers
And Chicago’s general rule (17th edition, p. 544) suggests writing out anything below 100:
In nontechnical contexts, Chicago advises spelling out whole numbers from zero through one hundred and certain round multiples of those numbers.
To be fair though, Chicago does offer an alternative rule similar to APA’s, spelling out only single-digit numbers (zero through nine) and using numerals for the rest.
To further complicate the issue, Nielsen Norman Group recommends using only numerals when writing for the web:
When writing for the Web, write numbers with digits, not letters.
So when it comes to writing out numbers, it’s mostly a style issue. Check which style guide your institution follows or whether they have their own internal style guide.
If it means anything, I prefer APA’s recommendation to use digits for anything 10 and above. I also follow Nielsen Norman’s recommendation for writing for the web.
Any questions? Ask me in the comments below.
