Readability checker for seven languages
Readability checker
Paste text, not HTML. A line break ends a sentence, so headings and list items count as sentences. Nothing leaves your browser.
The limits are editorial rules of thumb, not WCAG numbers: WCAG sets none for sentences or words.
The checker needs JavaScript, because it runs in your browser.
Paste a text to see the numbers.
An approximation: sentences are split by punctuation and syllables are estimated. Use it to compare versions of a text, not as a verdict. The related WCAG criterion is 3.1.5 Reading Level (level AAA): text that needs more than lower secondary education should have a simpler version or a summary.
Your text, long sentences marked
Long words
Possible passive voice
A hint for English only, found by a pattern: it misses some passives and can flag some that are not.
Paste a text, choose its language and see how it reads: the number of sentences and words, the average sentence length, the long sentences marked in your text, the long words, and for English and German a reading-ease score. Everything is calculated in your browser; the text is not sent anywhere.
What you get
- Sentences and words, with the average words per sentence and letters per word.
- Long sentences marked in your own text, each with its word count. The default limit is 25 words; change it in the field next to the text.
- Long words, from 13 letters by default, listed with how often they occur. In German, long compound nouns are normal; raise the limit there.
- A reading-ease score for English and German only, with the name of the formula.
- A passive-voice hint for English only.
A line break ends a sentence, so headings and list items count as sentences of their own.
The formulas, and how far to trust them
English: Flesch Reading Ease (Rudolf Flesch, 1948): 206.835 − 1.015 × (words per sentence) − 84.6 × (syllables per word). German: Amstad's adaptation (Toni Amstad, 1978): 180 − (words per sentence) − 58.5 × (syllables per word). Both read the same way:
| Score | Reading |
|---|---|
| 90 and up | Very easy |
| 80–89 | Easy |
| 70–79 | Fairly easy |
| 60–69 | Standard |
| 50–59 | Fairly difficult |
| 30–49 | Difficult |
| below 30 | Very difficult |
It is an approximation. The tool splits sentences by punctuation and estimates syllables with a rule of thumb, so a score can be off by a few points, and abbreviations, lists and numbers can confuse it. The formulas ignore the words themselves: a short sentence of rare words scores as easy. Use the number to compare two versions of the same text, not as a verdict about a reader.
For Ukrainian, Polish, Czech, Romanian and Russian the checker shows the lengths and the marked sentences but no score: we do not apply an English or German formula to other languages, and we only show a formula we can cite.
Readability and WCAG
The related criterion is 3.1.5 Reading Level, level AAA. It asks that text which needs more than lower secondary education to read has a simpler version or a summary. It is not part of level AA, which is the level of EN 301 549 and the European Accessibility Act, so a complex text does not by itself fail those. WCAG sets no limit for sentence or word length, and a score from this tool does not show whether 3.1.5 is met. The limits here are editorial rules of thumb.
Plain language still helps everyone: customers with dyslexia or a learning disability, people reading in their second language, and anyone reading on a phone. Short sentences, common words, one idea per paragraph and clear headings make a shop's delivery and returns pages easier to use. The criteria on language of the page and labels or instructions cover other parts of understandable content.
Reading level is a manual question
No tool can tell whether your text is understood. Ask someone who is not an expert to read the page aloud, and watch where they stumble. A free automatic scan of your site, such as the WCAG checker, finds missing labels, bad contrast and many other technical problems, but not unclear writing. It is an automatic check, not a full audit.
Frequently asked questions
Is my text sent to a server?
No. The text is analysed in your browser and is neither stored nor sent.
Which formulas do you use, and why only two languages?
Flesch Reading Ease (1948) for English and Amstad's adaptation (1978) for German. For the other languages we do not show a score, because we only use formulas we can cite and have not applied an English formula to them.
How accurate is the score?
It is an approximation. Sentences are split by punctuation and syllables are estimated, so it can be off by a few points. Use it to compare two versions of a text.
Does a good score mean my site meets WCAG?
No. WCAG 3.1.5 Reading Level is a level AAA criterion and sets no formula or number. The score is a hint for writing, not a test of conformance, and not legal advice.
Why is a sentence marked as long?
It has more words than the limit in the field next to the text, 25 by default. The limit is an editorial rule of thumb, not a requirement of WCAG.