Readability Checker
Flesch Reading Ease and Flesch–Kincaid grade level, scored live as you edit — with a plain-English verdict so the numbers mean something immediately.
Type at least one full sentence to score readability.
The formulas, in the open
Reading Ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words); Flesch–Kincaid Grade = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59. Both reward the same two habits — shorter sentences and shorter words — which is why the fastest route to a better score is splitting your longest sentence and swapping one latinate word ("utilize") for its plain twin ("use").
Frequently asked questions
What does the Reading Ease score mean?
A 0–100+ scale where higher is easier: 60–70 is "plain English" an 8th–9th grader follows comfortably, 30–50 reads like college material, and below 30 is dense academic or legal prose. Most successful general-audience writing lands between 60 and 80.
And the Flesch–Kincaid grade?
The same ingredients — sentence length and syllables per word — restated as a US school grade. An FK grade of 8 means an average 8th grader can follow it. Newspapers famously target around 9–11; plain-language guidelines for public information often require 8 or below.
How accurate is the syllable counting?
It is a heuristic (vowel groups with a silent-e rule), as in virtually every automated checker — English syllabification has genuine exceptions. Scores typically land within a few points of hand-computed values; treat the score as a strong signal, not a laboratory measurement.
Should I always aim for a higher ease score?
Aim for your audience. Simplifying a physics paper to 5th-grade prose destroys precision, and pushing marketing copy to graduate density destroys conversion. The score tells you where you are; where you should be depends on who is reading.
Scoring happens locally in your browser — nothing you paste is transmitted or stored. Syllable counting is heuristic, as documented on the methodology page.