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Readability Checker

Paste your text to see how hard it is to read, which grade level it suits, and which sentences to cut first. Scores update as you type.

Flesch Reading Ease

Higher is easier, on a 0–100 scale.

Average grade level

US school grade needed to follow the text.

Flesch-Kincaid Grade

Sentence length and syllables

Gunning Fog

Sentence length and complex words

SMOG Index

Words of three or more syllables

Coleman-Liau

Letters and sentences per 100 words

Automated Readability

Characters and sentence length

Words
Sentences
Words per sentence
Syllables per word
Complex words
Sentences over 25 words

What the scores measure

Readability formulas don't judge whether your writing is good. They measure two things that reliably predict effort for the reader: how long your sentences are, and how long your words are. Long sentences make readers hold more in mind at once. Long words tend to be less familiar. Cut either and the text gets easier.

The Flesch Reading Ease formula is 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words). The Flesch-Kincaid grade uses the same two inputs, scaled to a US school grade: 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59.

Reading the Flesch Reading Ease score

ScoreDifficultyReading level
90–100Very easy5th grade
80–89Easy6th grade
70–79Fairly easy7th grade
60–69Plain English8th–9th grade
50–59Fairly difficult10th–12th grade
30–49DifficultCollege
0–29Very difficultCollege graduate

How to make text easier to read

Start with the longest sentences listed above: splitting one 40-word sentence moves the score more than trimming ten words elsewhere. Then swap long words for short ones where the meaning holds: "use" for "utilize", "help" for "facilitate". Don't chase a number past the point where the writing loses precision. A score is a check, not a goal.

Need exact length limits for social posts or meta descriptions? Use the Word and Character Counter.

Frequently asked questions

What is a good readability score?

For writing aimed at a general audience, such as web pages, product copy and emails, a common target is a Flesch Reading Ease of 60 or higher and a grade level between 7 and 9. Specialist writing for an expert audience can reasonably score harder, as long as the difficulty comes from the subject rather than from long sentences.

Why do the grade-level formulas give different results?

Each formula measures difficulty differently. Flesch-Kincaid and SMOG count syllables, Gunning Fog counts words of three or more syllables, and Coleman-Liau and ARI count characters. Text full of short but uncommon words scores easier on syllable formulas than it really is. That is why this tool shows an average alongside each score.

How accurate is the syllable count?

Syllables are estimated with English spelling rules, not a dictionary. Unusual words and names can be off by a syllable, but over a few hundred words the errors average out and the scores stay close to dictionary-based tools.

How much text do I need for a reliable score?

At least 100 words, and ideally 300 or more. SMOG was designed for samples of 30 sentences, so treat it as a rough guide on shorter pieces.

Is my text stored or uploaded?

No. All analysis runs in your browser. Nothing you paste is sent to a server.