Readability Checker
Flesch Reading Ease and Grade Level for any text.
Check the readability of a piece of writing using the Flesch Reading Ease score and Flesch-Kincaid Grade Level — two widely used, well-established readability formulas.
The formulas
- Flesch Reading Ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)
- Flesch-Kincaid Grade Level = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59
Example: text averaging 15 words per sentence and 1.5 syllables per word scores 64.7 on Reading Ease and about grade 8. Stretch that to 25 words per sentence and 1.7 syllables per word, and it drops to 37.6 — around grade 14, college level.
What the scores mean
| Reading Ease | Difficulty | Typical reader |
|---|---|---|
| 90–100 | Very easy | 5th grade |
| 80–90 | Easy | 6th grade |
| 70–80 | Fairly easy | 7th grade |
| 60–70 | Plain English | 8th–9th grade |
| 50–60 | Fairly difficult | 10th–12th grade |
| 30–50 | Difficult | College |
| 0–30 | Very difficult | College graduate |
For most websites, emails and general information, aim for a Reading Ease of 60 or higher — about an 8th-grade level.
How to make writing easier to read
- Shorten sentences. Split any sentence longer than about 20–25 words.
- Choose shorter words: "use" instead of "utilize", "help" instead of "facilitate".
- Use active voice: "We fixed the bug" rather than "The bug was fixed by us".
- Break up long paragraphs and use lists for steps or options.
Readability scores measure sentence and word length, not meaning. Use them as a guide, and always read your text out loud for a final check.
Frequently asked questions
What is the Flesch Reading Ease score?
A score from 0-100 (higher means easier to read), based on average sentence length and syllables per word — developed by Rudolf Flesch in 1948 and still one of the most widely used readability formulas.
What is the Flesch-Kincaid Grade Level?
An estimate of the US school grade level needed to understand the text — e.g. a score of 8.0 suggests 8th-grade reading level.
How is syllable count estimated?
Using a vowel-group counting heuristic (counting groups of consecutive vowels, with common adjustments like silent trailing "e") — it's an approximation, not a dictionary lookup, so it can be slightly off for unusual words.
What readability score should I aim for?
For general audiences, a Flesch Reading Ease of 60–70 (about grade 8) is a good target. Technical or academic writing will naturally score lower.