Readability Score Checker
Score English text with Flesch Reading Ease, Flesch-Kincaid grade, Gunning Fog, Coleman-Liau and ARI, and find the sentences over 25 words.
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Input
Score the readability of English text
Output
Flesch reading ease 13 (very difficult)
| Words / sentences | 59 / 4 (14.8 words per sentence) |
|---|---|
| Flesch-Kincaid grade | 15.2 |
| Gunning fog | 16.1 |
| Coleman-Liau | 18.4 |
| Automated readability index | 14.9 |
All five formulas count only sentence length and word length, which is why they are rough: they cannot tell a familiar long word from an obscure short one, and they mis-score code, lists and headings. Use them to find the outliers, usually sentences over 25 words, and rewrite those. Technical writing for developers typically lands at grade 10-13; marketing copy should be lower.
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About this tool
Method, assumptions, practical next steps, and limits.
What the formulas measure
Every formula uses some mix of sentence length and word length, which is why they mostly agree and why they are rough. They cannot tell a familiar long word (information) from an obscure short one, and they score code, lists and headings badly. Use them to find outliers and compare drafts, not as a grade to hit.
Plain language
Short sentences and common words help every reader, including people reading in a second language. The US federal plain language guidelines give practical rules that go further than any score.