Readability Checker
Paste your writing to get six readability scores, a consensus grade level, and a highlighted view of long sentences and complex words
Text
Built for English. URLs and citations like [12] are ignored. Nothing leaves your browser.
Six Formulas, One Grade
Flesch, Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau and ARI, averaged into a single grade level
Highlighted Problem Spots
Sentences over 20 and 30 words are shaded, and words with three or more syllables are underlined
Private by Design
Your text is scored in your browser and never leaves your device
Frequently asked questions
What grade level should I aim for?
For general web content, aim for roughly grade 7 to 9, which is about what most adults read comfortably. Technical or legal writing often lands at 12 or higher, but shorter sentences and plainer words make it easier for everyone, including experts in a hurry.
Why do the six formulas give different scores?
They measure different things. Flesch, Flesch-Kincaid and SMOG lean on syllables, Gunning Fog on words of three or more syllables, and Coleman-Liau and ARI on letters per word instead. The consensus grade averages the five grade-level formulas so no single quirk dominates.
How accurate is the syllable count?
It is a heuristic: it counts vowel groups and adjusts for silent endings such as -e and -ed, with a short list of exceptions. Expect it to be off by a syllable on some words, which averages out over a few hundred words.
Why is SMOG marked low confidence?
SMOG was designed for samples of at least 30 sentences. On shorter text the score still runs, but a single long word can move it a lot, so treat it as a rough guide.
Does it work for languages other than English?
No. All six formulas and the syllable counter are tuned for English, so scores for other languages are not meaningful. URLs and numeric citations such as [12] are ignored before scoring.