QuickParaphrase

Readability checker

Paste your text to get the Flesch Reading Ease score, a grade level from five formulas, and the sentences that are hardest to read.

  • 6 formulas
  • Hardest sentences
  • Nothing uploaded

Scores appear as soon as you type a full sentence.

How the Flesch score works

Rudolf Flesch’s 1948 formula uses just two measurements: how long your sentences are and how long your words are (in syllables).

206.835 − 1.015 × words/sentence − 84.6 × syllables/word

Drag the sliders and notice the weights: adding one word to the average sentence costs about 1 point, but adding a tenth of a syllable to the average word costs about 8.5. Short, common words move the score far more than trimming sentences does, which is why swapping “utilize” for “use” works so well.

The Flesch–Kincaid grade level uses the same two inputs with different weights: 0.39 × words/sentence + 11.8 × syllables/word − 15.59.

60

Fairly difficult · readable by high-school students (10th–12th grade) · grade ≈ 9.9

Frequently asked questions

What is a good Flesch Reading Ease score?

For general audiences aim for 60–70 (“plain English”), which most 13–15-year-olds can read easily. Scores of 30–50 are typical for academic papers; below 30 is best understood by university graduates.

What is the Flesch–Kincaid grade level?

It converts the same two inputs (words per sentence and syllables per word) into a U.S. school grade. A score of 8.0 means an eighth-grader should be able to follow the text. It was developed for the U.S. Navy in 1975.

Why do the formulas give different grades?

They measure slightly different things. Flesch–Kincaid and Gunning Fog use syllables, SMOG counts words of three or more syllables, while Coleman–Liau and ARI use letters per word, which computers count more reliably. The average smooths out their differences.

Are readability scores reliable?

They are good at spotting long sentences and heavy vocabulary but know nothing about meaning, layout or the reader’s background knowledge. Use them as a signal, not a verdict. Syllable counts here are estimated by rule, so expect small differences from other tools.

Is my text uploaded?

No. All six formulas run in your browser.

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