Readability Analyser
Paste your writing and see how hard it is to read — six standard formulas, a plain-English grade level, and a sentence-by-sentence difficulty map that shows you exactly what to cut.
What the scores mean
Readability formulas estimate how much education a reader needs to understand a passage on the first try. Most do it from three things they can count: how long your sentences are, how long your words are, and how many of your words are "complex." None of them judge whether your writing is good — only how demanding it is to decode. Used well, they are a mirror, not a grader.
The grade-level formulas
Five of the six scores here output a U.S. school grade. Flesch–Kincaid Grade is the most widely used and combines sentence length with syllables per word. Gunning Fog works similarly but leans on the proportion of complex (three-or-more-syllable) words. SMOG counts polysyllabic words and is the formula health and medical writers tend to trust, though it is most accurate on passages of thirty sentences or more. Coleman–Liau and ARI are the odd ones out: they ignore syllables entirely and work from characters per word, which makes them more reliable on text where syllable-counting is shaky. The headline "consensus reading level" at the top is simply the average of these five, which smooths out the quirks of any single formula.
Flesch Reading Ease
The sixth score runs the other way. Flesch Reading Ease is a 0–100 scale where higher means easier. As a rough guide: 90–100 is very easy (around 5th grade), 60–70 is plain English that most adults read comfortably, 30–50 is difficult and college-level, and below 30 is very hard going. Much popular writing aims for 60 or above; this paragraph sits a little below that. Values can occasionally fall outside 0–100 for unusually simple or dense text.
The sentence difficulty map
Scores tell you how hard your writing is; the map shows you where. Each sentence is graded on its own and shaded if it runs long or dense — amber for hard, red for very hard. The usual fix is the simplest one: split a long sentence into two. Adverbs ending in "-ly" and likely instances of passive voice are flagged too, since both are easy wins for tighter prose — but they are suggestions, not errors. Plenty of good sentences keep an adverb or use the passive on purpose.
A note on syllable counting
English spelling and pronunciation don't line up neatly, so there is no perfect way to count syllables from text alone. This tool uses a well-established heuristic that is right the large majority of the time but will occasionally miscount an unusual word (it tends to over-count silent vowels and some endings). That means the syllable-based scores — Flesch, Flesch–Kincaid, Gunning Fog, SMOG — are best read as close estimates rather than exact figures. Coleman–Liau and ARI sidestep the issue by counting characters instead. Across a normal-length passage the small errors wash out, and the consensus grade stays dependable.
Privacy
Your text is analysed entirely in your browser. Nothing is uploaded, stored, or sent anywhere — the tool works with no network connection at all.