Readability Score Calculator
Calculate Flesch Reading Ease and Flesch-Kincaid Grade Level from any text.
What is the Readability Score Calculator?
This tool calculates two related readability metrics — the Flesch Reading Ease score and the Flesch-Kincaid Grade Level — both built from the same three underlying counts: words, sentences and syllables.
The formulas
Flesch Reading Ease: 206.835 − 1.015 × (Words ÷ Sentences) − 84.6 × (Syllables ÷ Words), scored 0–100 where higher means easier to read.
Flesch-Kincaid Grade Level: 0.39 × (Words ÷ Sentences) + 11.8 × (Syllables ÷ Words) − 15.59, giving an approximate U.S. school grade level needed to comprehend the text.
How to read the Reading Ease score
- 90–100: Very Easy (an average 11-year-old)
- 60–69: Standard
- 30–49: Difficult
- 0–29: Very Confusing (college graduate level)
A note on syllable counting
Syllables are estimated using a standard vowel-group heuristic, since there's no simple formula that's 100% accurate for every English word's true pronunciation — this is the same approach used by most readability tools, and it's accurate for the vast majority of common words.
Want the "why" behind this tool? Read What the Flesch Reading Ease Score Actually Measures.