Content Readability Score Calculator

A Score That Predates the Internet But Still Applies

The Flesch Reading Ease formula was developed in 1948 to gauge how difficult a passage of English text is to read, using nothing more than sentence length and syllable count. Decades later it's still one of the most widely used readability metrics for web content, because shorter sentences and simpler words reliably correlate with how easily a general audience can process a page — which matters for both user experience and how long visitors stay on a page.

The Formula

Score = 206.835 − (1.015 × Words per Sentence) − (84.6 × Syllables per Word)

Syllables are estimated with a vowel-cluster heuristic (counting groups of consecutive vowel sounds, with an adjustment for silent trailing "e"), so the count may differ slightly from a dictionary-exact syllable count on unusual words.

Where This Matters

  • Editing for a general audience — catching passages that have drifted into dense, jargon-heavy sentence structures before publishing.
  • Matching content to its audience — a landing page aimed at consumers benefits from a much easier score than a technical whitepaper aimed at engineers.
  • Comparing drafts — running two versions of the same paragraph through the formula to see which one actually reads more easily, rather than guessing.

Reading Ease Score Bands

Flesch Reading Ease score interpretation
ScoreDifficultyApproximate Level
90–100Very Easy5th grade
80–89Easy6th grade
70–79Fairly Easy7th grade
60–69Standard8th–9th grade
50–59Fairly Difficult10th–12th grade
30–49DifficultCollege
Below 30Very DifficultCollege graduate

How to Use This Calculator

  1. Paste the content you want to analyze into the text field.
  2. Select Calculate to get the Flesch Reading Ease score along with word, sentence, and estimated syllable counts.
  3. Compare the resulting difficulty level against your target audience and revise if the text reads more difficult than intended.

Related Calculations

Check the same draft's keyword usage with the Keyword Density Calculator, or verify your meta description length with the Meta Description Length Calculator.