Readability Score
Flesch-Kincaid and five other readability formulas.
Readability Score runs your text through Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, SMOG, Coleman-Liau and Automated Readability Index, and points at the specific sentences dragging the score down. Syllable counting uses a proper algorithm with an exceptions dictionary, not a vowel count. Your text is analysed in the page and never uploaded.
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How to use Readability Score
- Paste your text.
- Read the scores and the consensus grade level.
- Look at the flagged long or dense sentences and rewrite them.
Questions about Readability Score
What score should I aim for?
Flesch Reading Ease 60-70, roughly an eighth-to-ninth grade level, is the usual target for general web writing. Government plain-language guidance often asks for higher. Technical documentation for specialists can sit lower without being bad writing.
What are these formulas actually measuring?
Sentence length and word length, essentially. They do not understand vocabulary difficulty, logical structure or whether the argument makes sense — a text of short sentences full of jargon scores well and reads terribly. Use them as a smoke alarm, not a judge.
How are syllables counted?
With a rule-based algorithm handling silent e, diphthongs and common suffixes, plus a dictionary of the frequent exceptions English is full of. It is close but not perfect, which is inherent to counting syllables from spelling.
How much text does it need to be reliable?
At least a hundred words, and preferably several paragraphs. SMOG in particular was designed around samples of thirty sentences; on a single paragraph every one of these formulas swings on one long sentence.
Do the scores mean anything for text that is not English?
Not really. All six formulas were calibrated on English, and the syllable counting assumes English spelling. German or French text produces a number, but it does not carry the meaning it would for English.
Is Readability Score really free, with no limits?
Yes. There is no account, no daily cap, no file-size tier and no watermark, because there is no server cost to recover. The site is funded by clearly disclosed partner recommendations on the Partners page, never by metering the tools.
Are my files or text uploaded when I use Readability Score?
No. Everything is processed by JavaScript running in your browser, on your device. You can verify it: open your browser's developer tools, switch to the Network tab, and use the tool. You will see no request carrying your data — because there is nowhere for it to go.