Paste any text to see its Flesch–Kincaid Grade Level and Flesch Reading Ease score — two classic readability measures used by editors, teachers, and content teams to keep writing at the right level for its audience. Scores update instantly as you type.
How it works
The tool counts words, sentences, and syllables, then derives two averages: words per sentence and syllables per word. Syllables are estimated by counting vowel groups in each word. It then applies the two standard Flesch formulas:
- Flesch–Kincaid Grade Level = 0.39 × (words/sentence) + 11.8 × (syllables/word) − 15.59. The result is a US school grade, so 8.0 means an average 8th-grader can follow the text.
- Flesch Reading Ease = 206.835 − 1.015 × (words/sentence) − 84.6 × (syllables/word). Higher is easier; the scale runs 0–100.
Longer sentences and longer (more syllabic) words both raise the grade and lower the ease score.
Example
For the sentence “The cat sat on the soft warm mat.” there are 8 words, 1 sentence, and 8 syllables. Words/sentence = 8 and syllables/word = 1.0, giving a grade of 0.39 × 8 + 11.8 × 1 − 15.59 ≈ −1.5 (very easy, below grade 1) and a Reading Ease of 206.835 − 1.015 × 8 − 84.6 ≈ 114 (capped as extremely easy).
| Reading Ease | Level |
|---|---|
| 90–100 | Very easy (5th grade) |
| 60–70 | Plain English (8th–9th grade) |
| 30–50 | Difficult (college) |
| 0–30 | Very hard (graduate) |
All scoring happens locally in your browser — nothing is uploaded.