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Free Readability Checker

Check your text's Flesch Reading Ease and Flesch-Kincaid Grade Level scores to see how easy it is to read.

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Readability formulas estimate how easy a piece of text is to understand from two simple signals: how long its sentences are, and how many syllables its words have. They don't judge whether your writing is correct, persuasive or well-organized — only how much effort a reader needs to parse it.

This tool calculates two of the most widely used readability formulas, the Flesch Reading Ease score and the Flesch-Kincaid Grade Level, from text you paste in. The Reading Ease score runs from 0 to 100 (higher means easier to read), while the Grade Level estimates the US school grade a reader would need to follow the text comfortably.

How it works

Paste your text and the tool counts its words, sentences and syllables, then applies the standard Flesch Reading Ease and Flesch-Kincaid Grade Level formulas to those counts. You get both scores plus a plain-English difficulty label like "Standard" or "Difficult" so you don't need to interpret the raw numbers yourself.

  1. Paste your text.
  2. Click Check Readability.
  3. Review the Flesch Reading Ease score, Grade Level, and difficulty label.

Examples

Checking a marketing landing page

Short, punchy sentences with simple words score in the 70-90 range (Easy to Fairly Easy) — appropriate for a general consumer audience skimming quickly.

Checking a technical or legal document

Long sentences packed with multi-syllable terminology often score below 30 (Very Confusing) and correspond to a college-graduate reading level, which may be appropriate for a specialist audience but too dense for a general one.

Who should use it

  • Checking whether marketing or public-facing copy is easy enough for a general audience.
  • Verifying that educational material matches its intended grade level.
  • Comparing readability across drafts of the same document during editing.

Industry applications

  • Content writing and copywriting
  • Education and instructional design
  • Technical writing and documentation

Advantages

  • Gives both a 0-100 ease score and a plain grade-level estimate in one check.
  • Instant, with no signup or word limit up to 50,000 characters.
  • Uses standard, widely recognized Flesch formulas rather than a proprietary scoring system.

Limitations

  • Measures sentence and word complexity only — not grammar, tone, or actual clarity of meaning.
  • Syllable counting uses a heuristic and can be slightly off for unusual or foreign words.
  • Doesn't account for reader familiarity with domain-specific jargon.

Common mistakes to avoid

  • Treating a low Reading Ease score as inherently "bad" writing rather than checking whether it matches the intended audience.
  • Chasing an arbitrary target score by mechanically shortening sentences, which can produce choppy, unnatural writing.
  • Ignoring syllable-heavy jargon that a general audience won't recognize, even when sentences are short.

Best practices

  • Match the target score to your actual audience — technical documentation for experts doesn't need the same ease score as consumer marketing copy.
  • Use shorter sentences and simpler words where they don't sacrifice precision, especially for public-facing content.
  • Re-check readability after editing, since a single long sentence or dense paragraph can shift the score noticeably.

Tips

  • If your score is much lower than expected, check for a few unusually long sentences — they weigh heavily on the average.
  • Read the text aloud after checking — if it still sounds natural, don't over-simplify just to chase a higher score.

Frequently asked questions

Yes, with no signup and no limit on how much text you check.
It depends on your audience — general consumer content usually aims for 60-80 (Standard to Easy), while a score below 30 suggests text that only a specialist reader would find comfortable. There's no single universally "correct" score.
It estimates the US school grade level a reader would need to easily understand the text — a score of 8 roughly corresponds to 8th-grade reading level, for example.
No — it only measures sentence length and word complexity (via syllable counts), not correctness. Pair it with a grammar checker for a full writing-quality picture.
Flesch's formulas were designed decades ago to be calculable by hand from simple counts, and they've remained standard because they correlate well with perceived reading difficulty despite their simplicity — they're a proxy for complexity, not a complete quality measure.
Checks are linked to your browser session so you can revisit them — your text isn't shared with anyone else.

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