Taken, paraphrased and bastardized from the article “When Do I Spell Out Numbers?” dated February 13, 2017, by Brian A. Klems
The most common “rules of thought” on how to handle writing numbers are pretty simple:
- Spell out numbers under 10 (zero through nine)
- 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.
- 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.
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.
(Dan says: I DON’T 100% AGREE HERE): “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”) NO – Dan
- dates (February 14) YES – Dan
- monetary amounts ($8) NOT NECESSARILY; WHAT ABOUT FOURTEEN THOUSAND DOLLARS? SPELL IT OUT – Dan
- percentages (14 percent) YES – Dan
- and ratios (2-to-1) YES – Dan
Oh…
Dan Alatorre 
This is probably a slim occurrence exception but…in my spy novel I have a character who is counting to herself in all the languages she knows to kill time. And I spell out 41, 42, 43 as she gets to her destination in words in German.
So my exception would be: if the way a number is said matters, you should write it out.
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Right! I agree.
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I often try it both ways and see which I like best. I did not know there were rules. Yucky rules. Thanks for setting me straight.
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Yucky is right. Some things just look wrong when they’re done correctly. Who needs that!
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I have discussed this with other authors and someone said she spells most numbers out (including years) because, for e-books, if text to speech is enabled it helps the ‘robot reader’. So if you write 1976, for example, the robot would pronounce it differently. I can’t remember whether it would say ‘one, nine, seven, six’ or ‘ one thousand, nine hundred and seventy six’. Anyway, has anyone heard of this?
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Yeesh.
I’d rather not make my story clunkier for 99% of the readers in the hopes that 1% of them using computer readers can’t figure out 1-7-7-6 is 1776.
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The Associated Press Stylebook and The Chicago Manual of Style seem to be the standards and vary just a little. Here is a great link to 12 basic rules. http://www.grammarbook.com/numbers/numbers.asp
I think a lot will be forgiven if we strive for consistency, simplicity and to avoid redundancy.
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No doubt – although CMOS isn’t always right. It’s supposed to be, but it isn’t always. Sometimes its answers are just what I like to call correct but wrong. They may be technically accurate but nobody does it that way and my readers won’t understand it in its correct form… And mostly it just looks wrong to me so I say screw it!
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I agree, that’s why I think consistency is the best policy for a writer. A lot is over looked by a reader if we don’t make the reading too bumpy. LOL
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Yep.
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AP and Chicago differ–one says spell out up to 100. Also, the preference among publishers seems to vary between magazines/online versus books. Yes, it will drive you crazy if you’re going traditional. But if you’re self-publishing, who cares?
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It’s nutty.
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I don’t know if this is technically an exception, but I sometimes spell out numbers if they’re in dialogue. For some reason, it doesn’t look write to me to have a character saying a numeral. I hate rules anyway. I do think it’s important to know the rules, though, so you can break them the right way. You just don’t want to trip up your readers.
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Ha. Good point.
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I basically follow these guidelines, though if a number doesn’t require a hyphen I spell it out, even if greater than ten.
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When we were going over some numbers, we had one that was like $95,000 car, 500-year-old building, and my default position is this: I do talk to text and whatever it says to do, I start with that.
Rather, I go to that second because I pretty much use numbers instead of spelling them out first because I’m lazy!
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