Is it nine million or 9 million? “A picture is worth 1,000 words” or “A picture is worth a thousand words”?
To spell or not to spell a number? It’s an important question if you want your writing to be professional, consistent and appropriate for the setting. Not every instance will require adherence to standards, of course, but some use cases definitely require knowing these do’s and don’ts.
I kept this list to seven (not 7) items to keep things simple. There are far more recommendations on how to spell numbers in various ways. I’m sure I’ll give this more coverage in the future. But for now these six are a good place to start. These are the ones I probably use the most in day-to-day writing (other than numbers used for financial/business writing, which I’ll cover in the near future).
The authoritative sources don’t always agree. Heck, they don’t even agree on proper usage for the headline of this post. The Associated Press Stylebook recommends “do’s and don’ts” while The Chicago Manual of Style recommends “dos and don’ts.” But they’re excellent references that will help make your writing more consistent.
Remember the words of Norm Goldstein, a former editor of the APS: “I think if you’re going to be a good writer and if you want to be in [journalism], two things you have to remember are that there are some rules, and you ought to know them, and the second one is, if you want to break them, have a good reason.”
So, whether or not you should follow the APS or CMS depends on what you’re writing. You won’t need to be such a stickler if you’re composing an email, a memo, a PowerPoint presentation or some other business document. You probably wouldn’t need to spell the numeral 9 for something like “We signed 9 new clients last month.” The numeral is the most important thing in that sentence and should stand out. You might even want to bold the letter to draw more attention. Do what works best and looks best.
Something more formal, such as a white paper or report, might require following do’s and don’ts. Proper journalism and perhaps even blogging (depends on how formal) necessitates adherence to standards. You (and your editor) will want your writing to follow professional standards and have consistency to other articles. Sloppy use of numbers won’t reflect well on you or your publication.
1 Spelling numbers. The Associated Press Stylebook recommends spelling out numbers up to and including nine. That’s zero, one, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15 etc. For business writing, in some cases I think it’s OK to use a number in something informal, however. In an email, memo or presentation, I believe that writing “the company signed 9 new clients in February” is better than “the company signed nine new clients in February” because the number stands out amid the words — and the number 9 might be the single most important thing in that sentence. “We netted $5 million” is easier to read and appreciated than “We netted five million dollars.”
One obvious exception is a numbered list. In a typical use case, if you use a numbered list in Word, (rather than bullet points) the list will automatically list line items by 1,2,3,4, etc. instead of one, two, three, four, etc. (in these instances spelling numbers would look flat out silly).
The APS has two exceptions to spelling numbers:
2 Starting sentences with years. “1976 was an incredible year: Montreal hosted the summer olympics, Jimmy Carter was elected president of the United States, and Apple Computer Company was formed by Steve Jobs and Steve Wozniak.” (More on this below.) Any other number that starts the sentence should not be spelled, however.
3 Numbers in expressions should be spelled. “A picture is worth a thousand words.” “I feel like a million bucks.”
The Chicago Manual of Style recommends spelling numbers zero up to and including one hundred and using figures (1,2,3,4 etc.) after that. In addition, CMS recommends spelling whole numbers in combination with hundred, thousand, million, billion and so on ($1 million, $500 billion).
4 Normalization. Quick and Dirty Tips has a good example of what to do when two numbers refer to the same thing. “The snail advanced 1 inch on the first day and 12 inches on the second day.” In this sentence, “1 inch” and “12 inches” refer to the snail, so the numeral 1 is used instead of the word one.
5 If you don’t want to spell a number to begin a sentence, one option is to start the sentence with words instead of a year. I do this all the time because I don’t like the look of a sentence beginning with a year. There are always options. “The year 1982 was a great year for music.” “In fact, 1982 was a great year for music.” “Although 1976 is more revered in rock circles, 1982 was actually a great year for music.”
The APS recommends also spelling zero through nine for other types of numbers:
6 Ordinal Numbers. Spell first through ninth, then 10th, 11th, 12th, and so on.
7Addresses. For streets, spell First through Ninth (and capitalize them), then 10th, 11th, 12th, and so on.