According to Miss Snark - may her shadow never grow softer - a piece with 400 words may be counted by different programmes as anywhere between 386 and 408 words.

I'm too tired to do the maths, but if you have the 386-programme and write up to what it says is 400, and the competition has the 408 programme, only we're talking about a 5,000 word story, that's quite a difference, and I suppose could get your story disqualified.

Details, and her conclusion, here:

http://misssnark.blogspot.com/

I think I'll stick to novels. No-one counts them with a fine-toothed comb.

Emma