This free tool measures how easy your writing is to read. Paste a paragraph, an email, or a full draft below, and it computes two standard readability scores — the Flesch Reading Ease and the Flesch–Kincaid Grade Level — along with the word, sentence, and syllable counts behind them. Everything runs entirely in your browser. Nothing you paste is uploaded, stored, or sent anywhere, and the tool sets no cookies.
Analysis updates as you type. Nothing leaves your browser.
Results
How it works
The tool implements two readability formulas that are real, published, and widely used. Both rely on the same three measurements — total words, total sentences, and total syllables — which it counts directly from your text.
Flesch Reading Ease was developed by Rudolf Flesch in 1948. It returns a score from roughly 0 to 100, where a higher number means easier reading. The formula is 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words). Standard interpretation bands:
- 90–100 — Very easy (around 5th-grade reading level)
- 80–90 — Easy
- 70–80 — Fairly easy
- 60–70 — Plain English (8th–9th grade)
- 50–60 — Fairly difficult
- 30–50 — Difficult (college level)
- 0–30 — Very difficult (college graduate)
Flesch–Kincaid Grade Level was developed by J. Peter Kincaid and colleagues in 1975 under a U.S. Navy contract. It restates readability as a U.S. school grade level using 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59. A result of 8.0 means the text should be understandable to an average 8th-grade student.
Syllables are estimated with a standard English heuristic: each word is lowercased, its vowel groups (a, e, i, o, u, y) are counted, a silent trailing "e" is subtracted, and every word is credited with at least one syllable. Heuristics like this are close but not perfect on irregular words, so treat the scores as a strong guide rather than an exact verdict. The tool also flags sentences longer than 25 words, since over-long sentences are one of the most common drags on clarity.
CommunicationAbility is reader-supported and editorially independent; we accept no sponsorship or paid placement. This tool provides general readability information for self-editing and is not a substitute for professional editorial judgment. Terms apply.
Tool reviewed: June 26, 2026