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Readability Score

Check your text’s Flesch Reading Ease and Flesch-Kincaid grade level.

Flesch Reading Ease

Enter at least one sentence.

A readability score rates how hard text is to read from average words per sentence and syllables per word. Flesch Reading Ease runs 0–100, where higher is easier and 60–70 is plain English; Flesch-Kincaid converts the same inputs into the US school grade needed to read it.

Reading ease and grade level

Both scores come from the same two ratios — average words per sentence and average syllables per word. Flesch Reading Ease runs 0–100, where higher is easier and 60–70 is plain English. Flesch-Kincaid grade level rescales the same inputs into the US school grade needed to read the text comfortably. To check the sentence and word totals the formulas rely on, the word counter reports them as you type.

ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)

Flesch Reading Ease; grade level = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59

Worked example

A passage with 20 words across 2 sentences and 30 syllables — so 10 words per sentence and 1.5 syllables per word:

  1. 1
    Find the two ratios. Words per sentence: 20 ÷ 2 = 10. Syllables per word: 30 ÷ 20 = 1.5.
  2. 2
    Compute Reading Ease. 206.835 − 1.015 × 10 − 84.6 × 1.5 = 206.835 − 10.15 − 126.9 = 69.8 (standard / plain English).
  3. 3
    Compute the grade level. 0.39 × 10 + 11.8 × 1.5 − 15.59 = 3.9 + 17.7 − 15.59 = 6.0, about US grade 6.

Reading Ease bands

Flesch Reading Ease ranges and roughly who can read them.

ScoreDifficultyAudience
90–100Very easyGrade 5
60–70StandardGrade 8–9, general public
30–50DifficultCollege
0–30Very difficultUniversity graduate

How to improve a low score

Shorten sentences. Words per sentence weighs heavily in both formulas — splitting one long sentence into two raises the ease score directly.

Choose shorter words. Fewer syllables per word lowers the second term, so swapping “utilize” for “use” nudges the score up.

Treat it as a guide. Syllables are estimated with a vowel-group heuristic, so the score is a close approximation, not a verdict — readability never replaces a careful read-through.

How are syllables counted?
With a vowel-group heuristic — close for most English text, though no algorithm is perfect.
What score should I aim for?
For general audiences, a Reading Ease of 60+ (around grade 8) is a good target.
What is the difference between the two scores?
Reading Ease is a 0–100 scale where higher is easier; the grade level translates the same inputs into a US school grade. They move in opposite directions.
How do I raise the Reading Ease score?
Use shorter sentences and simpler, fewer-syllable words — both ratios in the formula then improve.
Why does my score differ from another checker?
Syllable counting and sentence detection vary between tools, so scores differ by a point or two on the same text.
What does a Flesch Reading Ease score of 0 or 100 mean?
The scale runs 0–100: scores near 90–100 are very easy (around grade 5), while scores near 0 are very difficult, typically requiring a university-graduate reading level.