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Readability Checker
Score how easy your writing is to read: Flesch, grade levels, hard sentences and a bionic reading view.
Free, no uploads, no sign-up. Runs 100% in your browser.
How Readability Checker works
Your text is split into sentences, words and syllables, then six standard formulas are applied: Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau and ARI. Long sentences and sentences with a high grade are listed so you know what to rewrite. The bionic view bolds the start of each word to guide the eye.
Input: Text, TXT, MD. Output: HTML.
How to use Readability Checker
- Paste or open your text.
- Read the ease score and the grade level.
- Rewrite the hard sentences listed under the scores, and watch the score change as you type.
Tips
- Aim for an ease score of 60 or more for a general audience.
- Short sentences and short words raise the score the most.
Readability Checker FAQ
- Which languages does it support?
- The formulas were made for English. Other languages still get word and sentence counts, but the grade levels are only a rough guide.
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
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