Readability Checker

How Readability Checker works

Score any text with Flesch Reading Ease and grade level, plus words per sentence and syllables per word. Everything happens inside this page: the tool reads your input, runs the calculation or conversion locally, and hands the result back to you. Nothing is transmitted, because there is no backend to transmit it to.

That design choice is deliberate. Most free tool sites upload your files to a server, process them there, and quietly keep a copy. Toolcin cannot do that — the site is a set of static files. If your connection dropped the moment the page finished loading, every tool would still work.

Flesch Reading Ease

The score is 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words). Higher is easier: 90–100 reads like a children's book, 60–70 is plain English, below 30 is academic.

Syllables are estimated with a vowel-group heuristic, not a dictionary. That is why the score is a reliable comparison between two drafts and only an approximate absolute measure.

The grade level and the practical target

Flesch–Kincaid grade level converts the same inputs into a US school year. Grade 8 is the usual target for public-facing web copy; grade 12 is a newspaper feature.

Two levers move the score: shorter sentences and shorter words. Sentences are easier to fix, and they are also the ones readers notice.

What it cannot measure

Whether the writing is any good, whether the argument makes sense, and whether the jargon is appropriate for the audience. A technical document for engineers scores badly and is still correct.

Use it as a smoke test for accidental density, not as a writing standard.

Good to know

• Works offline once loaded, including on flights and in locked-down networks.
• No file size limit beyond your device's own memory.
• Free to use, with no account and no usage counter.
• Results are produced locally, so they are not logged or shared with anyone.

Questions