How to use the Readability Checker
- Paste a few paragraphs of English text.
- Read the Flesch reading ease score and grade levels.
- Rewrite the highlighted hardest sentences, then check again.
What does this tool do?
Readability formulas estimate how hard text is from sentence length and word length (in syllables or letters). The Flesch reading ease score runs from 0 to 100 — higher is easier. Grade-level formulas convert the same signals into US school grades.
Formulas can't judge clarity, structure or meaning, but long sentences and long words reliably make text harder to read, so they're a useful check.
Why use it?
- Write for a general audience (aim for grade 7–9).
- Make support articles and instructions clearer.
- Compare drafts objectively.
What the scores mean
Flesch reading ease bands:
| Score | Difficulty | Typical reader |
|---|---|---|
| 90–100 | Very easy | Age 11 |
| 70–80 | Fairly easy | Age 12–13 |
| 60–70 | Plain English | Age 13–15 |
| 50–60 | Fairly difficult | High school |
| 30–50 | Difficult | College |
| 0–30 | Very difficult | Graduate |
The formula
Flesch ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)
Flesch–Kincaid grade = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59
Accuracy and limits
- Syllables are counted with an English heuristic, which is accurate to within about one syllable per word.
- Scores are designed for English and aren't meaningful for other languages.
Privacy
Everything you type is processed in your browser. Nothing you enter is sent to our servers or stored by us. There's no account to create and nothing to install.
Last reviewed by the M2Toolkit team.