How readability checkers work
They’re assessing the ‘reading age’ someone needs to be to understand your writing clearly on a first reading. All readability formulas work by counting the variables that have the biggest impact on readers being able to ‘take in’ a bit of writing: sentence length, number of syllables per words, number of passive sentences. (They don’t check for spelling mistakes though.) Each formula works things out in a slightly different way. We’ve listed below how to interpret the various formulas – and if you want a cheat’s guide, a score of about 65 is good for business writing.
But remember, the score doesn’t tell you everything.
Readability formulas are excellent when you need your writing to be understood by a universal audience (say, instructions that come with medicine), and to meet ‘industry benchmarks’ (some US states have set a grade for all insurance documentation).
For the rest of us, they’re a good rule of thumb as to whether your writing’s on track. But they’re a blunt instrument. It’s probably already occurred to you that some long words (‘hippopotamus’, with five syllables) aren’t ‘difficult’, and that a well-crafted long sentence may well be easier to read than poorly thought-through short ones.
Readability formulas can also only tell you how easy or hard your writing is to ‘take in’. They can’t tell you anything about whether your logic is sound or wonky, your arguments forceful or weak, your metaphors fresh or stale, or your jokes funny or flat. So, if you want an expert opinion, give us a call. We can give feedback and advice, or write, rewrite or edit just about anything.