Free readability checker
Paste your text to get its Flesch Reading Ease score and Flesch-Kincaid grade level, the average sentence length, and every sentence over 25 words highlighted in place. It also estimates passive voice and the share of sentences that use transition words. Scores update as you edit, so you can see what splitting a sentence does.
Flesch Reading Ease 79, Fairly easy. Grade level 5.5. 1 sentence over 25 words.
- Flesch Reading Ease
- 78.8Fairly easy: US 7th grade
- Flesch-Kincaid grade
- 5.5US school grade
- Average sentence
- 12.9words
- Over 25 words
- 1of 8 sentences
- Passive voice (estimate)
- 38%3 sentences
- Transition words
- 25%2 sentences
Highlighted sentences run over 25 words.Dotted underline marks possible passive voice.
Search engines read your page before anyone else does. They do not grade your prose, but people do.
When a paragraph is written in long, winding sentences that stack one qualification on top of another, readers who arrived from a search result on a small phone screen tend to give up long before they reach the point you were trying to make. Short sentences help. So do clear verbs.
The report was reviewed by the team and several changes were requested. However, most of them were small. For example, the intro was cut in half and the jargon was replaced with plain words.
- One sentence runs over 25 words, the longest at 44. Split at an “and”, “which” or “because”, or move a qualification to its own sentence.
- Passive voice is flagged by a pattern (a form of “to be” followed by a past participle, such as “was reviewed”). It misses some passives and catches some adjectives, so treat each mark as a sentence to reread, not an error. Passive is the right choice when the actor is unknown or unimportant.
- Readability scores are writing aids, not Google ranking factors. Aim for text your actual readers can follow; a legal guide and a recipe should not score the same.
What the scores measure
Both formulas look at only two things: how many words a sentence has, and how many syllables a word has.
- Flesch Reading Ease = 206.835 - 1.015 x (words per sentence) - 84.6 x (syllables per word). Higher is easier.
- Flesch-Kincaid Grade = 0.39 x (words per sentence) + 11.8 x (syllables per word) - 15.59. The result is a US school grade.
| Reading Ease | Reads as | Roughly suits |
|---|---|---|
| 90 to 100 | Very easy | Age 11 |
| 70 to 89 | Easy to fairly easy | Ages 12 to 13 |
| 60 to 69 | Plain English | Ages 13 to 15 |
| 50 to 59 | Fairly difficult | Ages 15 to 18 |
| 30 to 49 | Difficult | College |
| 0 to 29 | Very difficult | College graduates |
Syllables are estimated with English spelling rules, so expect small differences from other tools. The formulas cannot tell whether a text makes sense, only whether its sentences and words are short.
Readability and SEO
Readability scores are not Google ranking factors, and no search engine grades pages by reading level. They are writing aids. They matter indirectly: people leave pages they struggle to follow, and short, self-contained sentences are easier to scan, to translate and to quote accurately.
Pick a level for your audience rather than a universal target. Plain English, around 60 or above, suits most consumer pages; a tax guide or API reference can be harder because its readers expect precise terms. When a score is low, the fix is nearly always the same: split long sentences and swap long words for short ones where the meaning survives. For posts that have slipped over time, see refreshing old posts.
Passive voice and transitions: reread, do not chase
Passive voice is flagged by a pattern: a form of "to be" followed by a past participle, as in "the report was reviewed". The pattern misses passives without "be" ("got approved") and catches some adjectives, so treat each mark as a sentence to reread. Passive is often right, for example when the actor is unknown or beside the point.
Transition words such as "however", "for example" and "as a result" tell the reader how one idea leads to the next. A very low share in a long text can mean the paragraphs read as disconnected statements. Adding "furthermore" to every sentence does not help.
In WordPress, the free Hydrogen SEO plugin includes average sentence length in each post's on-page score, so long sentences get caught before you publish.
Common questions
What is a good Flesch Reading Ease score?
For general web content, 60 or higher (plain English) is a sensible aim. Specialist content for experts can score lower and still be the right choice for its readers.
Why do readability tools give different scores?
They split sentences and count syllables in slightly different ways, especially around headings, lists, numbers and abbreviations. Compare scores from the same tool over time rather than across tools.
Is passive voice bad for SEO?
No. Search engines do not penalize passive voice. Active sentences are often shorter and clearer, which helps readers, but passive is fine where it reads naturally.
Does it work for languages other than English?
The scores use the English formulas and English syllable rules, so results for other languages are not meaningful. Several languages have their own adaptations, such as the Amstad formula for German and Fernández Huerta for Spanish.