When Do I Spell Out Numbers? (Grammar Rules)
There are several rules of thought on how to write numbers, but the most common is pretty simple. Here’s when you should spell out numbers and when you shouldn’t.
Q: Sometimes I see numbers spelled out (nine) and at other times I see them in numeric form (9). Which is correct? When do I spell out numbers and when do I write them out? —Kevin T.
A: Most writers—including me—took on this artistic profession for three reasons: We’re creative, we love to read and, most important, we want to avoid numbers at all costs. Yet somehow, even in writing, numbers have found a way to sneak back into our lives.
There are several rules of thought on how to handle writing numbers, but the most common is pretty simple. Spell out numbers under 10 (zero through nine), and use the numeric symbols for numbers 10 and up. I bought eight candy bars from the vending machine. I average eating 29 candy bars per month.
There are some exceptions to the rule. For example, spell out all numbers that begin a sentence. Forty-seven-thousand contestants were turned down for “American Idol.”Eleven were selected. Of course, there’s an exception to the exception: Don’t spell out calendar years, even at the front end of a sentence. 1997 was the year I met my wife. And, if you don’t feel like writing those long, awkward-looking numbers, just recast the sentence. American Idol turned down 47,000 contestants. I met my wife in the magical year of 1997.
Also, there are other instances where the under-10/over-10 rule doesn’t apply. Always use figures for ages of people (“He’s 9 years old”), dates (February 14), monetary amounts ($8), percentages (14 percent) and ratios (2-to-1).
Again, this is a style issue and other sources may suggest different ways of handling numbers. So please, no hate mail. And let’s agree not to talk about numbers for the rest of the day—they make my head hurt.
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Brian A. Klems is the former Senior Online Editor of Writer’s Digest, and author of Oh Boy, You’re Having a Girl (Adams Media/Simon & Schuster). Follow him on Twitter @BrianKlems.