HelperCrateReadability Score
Check Flesch Reading Ease and Flesch-Kincaid grade level for your text.
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What Readability Score does
Readability Score estimates how easy a passage is to read using two classic formulas: Flesch Reading Ease and the Flesch-Kincaid grade level. Paste a draft and click Analyze to see the word, sentence and syllable counts behind the scores, plus a plain-language interpretation of the result.
Flesch Reading Ease returns a number where higher is easier; in the usual interpretation, 60 to 70 counts as plain English. Flesch-Kincaid maps the same counts to a rough United States school grade, so grade 8 means approximately the level of an eighth-grade student. Real measured examples on this page: the three short sentences “The cat sat on the mat. The dog ran fast. We had fun.” score 117.8 (Very easy) at grade K, while a deliberately dense 13-word sentence scores minus 125.2 (Very difficult) at grade 34.
Readability is a property of the text, not a judgement of it: the formulas only reward short sentences and short words, so use the numbers to spot passages that are denser than you intended rather than as a verdict on quality.
How to use Readability Score
- Paste the text into the box.
- Click Analyze — the tool scores on demand rather than on every keystroke.
- Read Words, Sentences and Syllables, the raw counts that feed both formulas.
- Check Words/sentence and Flesch Reading Ease: 60 or above is plain English, below 50 is heavy going.
- Use Grade Level as a rough United States school grade, from K through the teens and beyond.
- Read the interpretation line for the band, then rewrite the longest sentences or replace long words to lift the score.
Features
- Flesch Reading Ease and Flesch-Kincaid grade level computed from the same counts.
- Word, sentence and syllable totals, plus words per sentence.
- Interpretation bands from Very easy (90 and above) down to Very difficult (below 30).
- Counts words as runs of Unicode letters and digits, so non-Latin scripts count too.
- Sentences are found by runs of full stops, question marks or exclamation marks.
- Everything runs in the page — no text is uploaded, and nothing is stored.
Tips and common mistakes
- The syllable counter is a heuristic, not a dictionary: words of three letters or fewer count as one syllable, common silent endings such as es, ed and a final e are trimmed, a leading y is dropped, and the remaining vowel groups (a, e, i, o, u, y) are counted. Unusual words can be wrong by a syllable in either direction.
- Only the letters a to z are used in that step, so accented letters are ignored and texts in languages other than English are not measured meaningfully.
- The formulas were designed for English prose; scores for other languages, code or data should not be trusted.
- A sentence needs a terminator followed by a space or the end of the text; a fragment with no punctuation counts as one sentence, which is why even a single word produces a full set of scores.
- Headings, numbered lists and tables skew the estimate because they have no sentence punctuation — score prose paragraphs rather than the whole document.
Frequently asked questions
What do the two scores mean?
Flesch Reading Ease rates how easy the text is on a rising scale where higher is simpler, and Flesch-Kincaid converts the same counts into a United States school grade. They share the same inputs and usually move together, so shortening sentences and words helps both.
Where do the interpretation bands come from?
They are the conventional Flesch bands: 90 and up Very easy, 80s Easy, 70s Fairly easy, 60s Plain English, 50s Fairly difficult, 30s Difficult and below 30 Very difficult. The grade shown is the Flesch-Kincaid result rounded to a whole number, with K for scores below grade 1.
Why can a score be negative or above 100?
The formulas are linear and unbounded. Text that is far easier than the scale assumes can exceed 100, and a few very long words in a very long sentence can drive the score below zero. The interpretation bands still apply: anything under 30 counts as Very difficult.
Does it check spelling or grammar?
No. It counts words, sentences and syllables and applies the formulas; it does not read the text or know whether it makes sense. A nonsense sentence built from short words can score better than a clear sentence containing one long technical term.
Why might the word or syllable counts look wrong?
Words are runs of Unicode letters and digits with apostrophes and hyphens included, so “well-known” is one word. Syllables come from a heuristic that strips accents and common endings, which can over- or under-count unusual words, abbreviations and names.
Is my text stored anywhere?
No. Everything is computed in your browser from the textarea contents, and nothing is uploaded or saved.
Related text tools: Word Counter, Markdown Editor, HTML ↔ Markdown, Case Converter.
Scoring happens entirely in your browser — your text is never uploaded or stored.