How do you decide when to write a number as a number or as a word?

Examples:

He was 28 years old.
He was twenty-eight years old.

The house was worth over ten million pounds.
The house was worth over £10,000,000.
The house was worth over 10 million pounds.

I feel personally it looks neater to always express them as words. What are your thoughts? I presume there are no hard-and-fast rules but I suppose there are conventions (that I don't know about).

Hart's Rules will give you standard UK practice, and the main US variants. Off the top of my head numbers in fiction. It'll vary slightly too with the house style of different publishers, but that's a copy-editor's problem not yours. I think it's usual to spell out numbers up to a hundred, and write them as figures above that. But 'spell out' of course includes ten million, if you see what I mean, because it's 'ten'.

Emma

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Sorry, bit of a mess there, after a cut-and-paste. But you get the idea.

I don't know what's common in fiction, but I think the main thing to focus on with this, Tim, is consistency. Consistency looks professional. If your own system is consistent and logical, and doesn't look too weird, then the publisher will change it to their house style later on and you needn't worry.

When I sub-edited computer mags we would use words for numbers up to ten, and then figures for 11 onwards. I agree with Emma that you could choose to write ten million could be in words because you can view is as ten of something called million (which is sort of true).

There are lots of issues to do with longer numbers, because how complex the number is affects which way is quicker to write it. For instance, 10,000,000 is harder to read than 'ten million', but 24,879,456 is easier to read than if you spelled that out in words, which would be horrendously long-winded. So bear that in mind and I'd advise keeping it as short and easy to read as possible, whichever method that gives rise to.

I'd also bear in mind how we're used to a number being expressed in a certain context. For instance, with house prices we're used to seeing them as £385,000, so that might make a difference to how you choose to express it too.

Deb

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Or even, if I'd checked what I wrote: '...you could choose to write ten million in words because you can view it as ten of something called million'

Just found Hart's Rules, and it confirms that a) house style is king, and b) Deb and I are right, in that (at OUP, at least) in non-technical writing they spell-out up to a hundred and in technical writing up to ten. Also things like 'thirty 10-page pamphlets' is clearer than the alternatives. Also 'about a thousand' is better than 'about 1000' when the number's not exact anyway, and also in phrases like, 'a thousand and one odds and ends'. Lots more in that chapter, but mostly not relevant to fiction.

I do remember a long thread on WW, though, about house numbers, where despite the 'spell out up to a hundred' rule, it looks odd to write 'she lived at number seventy-seven' when we'd all see that as No.77. True of bus-numbers too. Can't remember what the answer was, though really, again, it's a copy-editor's worry: all you need to be is consistent.

Emma

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Oh, and FWIW, in your example, DrQ, Hart's Rules says that 'more than a million pounds' is traditionally prefered to 'over a million pounds', except when referring to age. But that would depend on the voice of your narrative, of course.

Thanks for the replies, that's really helped me. I think I would have expressed a house number as the actual number. It's funny how often your instinct is right; I suppose the subconcious leanrs something from all those books you read!

Thanks again.

Tim, I agree about instincts often being right. It's often about how most people would expect to see it - and a house number you expect to see as figures, on envelopes and on the number on the front door itself.

Interesting info, Emma.

Deb