Flesch Reading Ease Calculator
A Readability Score From Sentence and Word Length
Flesch Reading Ease is one of the oldest and most widely used readability formulas, built on a simple insight: longer sentences and longer (more syllable-heavy) words both make text harder to read. Rather than judging readability subjectively, the formula converts those two measurable quantities into a single score, with higher numbers meaning easier text.
The Formula
Score = 206.835 − (1.015 × Words/Sentence) − (84.6 × Syllables/Word)
Scores run roughly from 0 to 100+ and map to standard reading-level bands, from "Very Easy" text a 5th grader can follow to "Very Confusing" text suited to college graduates.
Where This Matters
- Writing for a general audience — consumer-facing content (instructions, marketing copy, support articles) generally targets a higher, easier score than academic writing.
- Plain-language compliance — some government and legal documents are required to meet a minimum readability score for public accessibility.
- Editing long or dense sentences — a low score often points directly at overly long sentences or unnecessarily complex vocabulary that could be simplified.
Score Interpretation
| Score | Reading level | Approx. grade |
|---|---|---|
| 90–100 | Very Easy | 5th grade |
| 80–89 | Easy | 6th grade |
| 70–79 | Fairly Easy | 7th grade |
| 60–69 | Standard | 8th–9th grade |
| 50–59 | Fairly Difficult | 10th–12th grade |
| 30–49 | Difficult | College |
| 0–29 | Very Confusing | College Graduate |
Worked Examples
| Text profile | Words/Sentence | Syllables/Word | Score |
|---|---|---|---|
| Simple, short-sentence text | 10.0 | 1.40 | 78.25 (Fairly Easy) |
| Dense, long-sentence text | 22.0 | 1.70 | 40.69 (Difficult) |
How to Use This Calculator
- Paste or type your text into the text box.
- Select Calculate to see the Flesch Reading Ease score and its reading-level interpretation, along with the underlying words/sentence and syllables/word figures.
Related Calculations
Compare against the Gunning Fog Index Calculator for a different readability formula, or check SMOG Index Calculator for a grade-level estimate designed for longer samples.