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Readability Checker
Paste your writing to get a Flesch Reading Ease score and a Flesch–Kincaid grade level. Both are calculated with plain arithmetic from sentence length and syllable counts — there is no AI involved and nothing is sent anywhere.
—Reading ease
—Grade level
—Interpretation
0Words
0Sentences
0Syllables
0Avg words / sentence
How to read the score
- 90–100 — very easy. Understood by an average 11-year-old.
- 80–89 — easy. Conversational English.
- 70–79 — fairly easy.
- 60–69 — plain English, understood by 13–15 year olds. This is the target for most web writing.
- 50–59 — fairly difficult.
- 30–49 — difficult, typical of academic prose.
- 0–29 — very difficult, best understood by graduates.
The formula, and what it actually measures
Flesch Reading Ease is 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words). Only two things move the number: how long your sentences are, and how many syllables your words have.
That is a real limitation worth understanding. The formula cannot tell whether your writing is clear — only whether it is short. A passage of confident nonsense in brief words scores brilliantly. Use the score to catch bloated sentences and needlessly Latinate vocabulary, not as proof that your meaning landed.
How to raise a low score
- Split your longest sentences. This moves the number more than anything else. Find every sentence over 25 words and look for a comma or conjunction to break at.
- Swap long words for short ones. "Use" for "utilise", "help" for "facilitate", "about" for "approximately". Syllables per word is the second lever.
- Cut hedging. "It should be noted that" and "in order to" add syllables and say nothing.
- Use active voice. Passive constructions add words without adding meaning.
- Do not chase the number blindly. Legal, medical, and technical writing legitimately scores lower because the required terminology is polysyllabic. Fix the sentences, keep the terms.