Six readability formulas at once — and the exact sentences that are dragging your score down.
A readability score tells you how much effort your reader has to spend. This checker runs the six formulas people actually cite — Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, SMOG, Coleman-Liau and ARI — on the same text at once, so you see whether they agree. A number on its own doesn't help you fix anything, so the tool also highlights every sentence that is too long or too dense, and shows you the hardest words it found. Fix those and the score follows.
Flesch Reading Ease runs from 0 to 100 — higher is easier. Aim for 60–70 for general web copy (about a 9th grade level); news sits near 60, legal and academic writing often drops under 30. The others report a US school grade: a Flesch-Kincaid of 8 means an average 13-year-old can read it. Marketers are usually told to target grade 6–8, which sounds insultingly low until you remember that easy prose is read faster, not read down to.
Every one of these formulas is a rough proxy: they count syllables, words and sentences, and they cannot tell whether you are making sense. You can score 90 with fluent nonsense, and a brilliant paragraph can score 40 because of one long quotation. They are also English-only — they were calibrated on English and count syllables with English patterns, so German or Ukrainian text produces a number that means nothing. Rather than show you a confident wrong score, this tool detects non-English text and tells you. Use the score as a smoke alarm, not a grade.
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