Teachers and students
Check whether a discussion section has drifted into sentences that hide the result. A high grade level is sometimes appropriate and sometimes just tangled.
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Free Readability Checker
See how difficult a passage is to read. The checker calculates Flesch Reading Ease, average sentence length, and the share of complex words — entirely on this page, with no AI request.
Measure this passage
Calculated in your browser. Nothing is uploaded.
Flesch Reading Ease
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Paste text
- Reading difficulty
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- Avg. sentence length
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- Word complexity
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- Grade level
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Paste a paragraph to calculate reading ease, sentence length, and word complexity.
Word complexity is the share of words with three or more syllables. Syllable counts are estimates.
How it works
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The score updates as you type
Flesch Reading Ease uses sentence length and syllables per word. Higher scores are easier to read. A score around 60 is ordinary prose for a general audience.
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Sentence length and complexity sit beside it
Average sentence length shows whether the draft is a chain of long clauses. Word complexity is the percentage of words with three or more syllables.
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Use the number to choose a revision, not a grade
A methods section should not score like a children’s book. The useful question is whether this audience can follow this paragraph.
When to use it
Public explanations
Health, legal, and government writers can see when a public note has climbed into “very difficult” without meaning to.
Editing for rhythm
If the average sentence is long and the complex-word share is high, split one sentence and replace one abstract noun before you rewrite the whole piece.
Limits and accuracy
- Syllable counts are estimates. Names, acronyms, and hyphenated terms can move the score.
- The formula was built for English prose. It is a poor fit for poetry, code, and reference lists.
- A high score is not automatically better. Specialist writing is allowed to be dense when the audience expects it.
- Nothing is uploaded. The math runs in your browser.
Examples
A public sentence
“Drink water when you are outside in the heat” uses short words and one clause. It lands in the easy range, which is what a heat warning wants.
A methods sentence
A sentence that stacks “operationalization,” “participants,” and a long relative clause will score as difficult even if a specialist can read it. The checker is telling you about load, not about correctness.
Questions about this tool
For a general audience, 60–70 is a common target. Student essays often sit lower. A score under 30 is very difficult and worth a second look unless the readers are specialists.
If the score is hard to read, change the voice — not just the commas.
Splitting sentences helps. When the draft also needs to sound like a person in your field, the humanizer can rewrite it without throwing out the point.