Check the grade level and readability of your writing
Updated October 2026
| Score | Formula | Reads as |
|---|---|---|
| Flesch Reading Ease | 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words) | 0–100, higher is easier |
| Flesch-Kincaid Grade | 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59 | U.S. school grade |
| Gunning Fog | 0.4 × (words per sentence + 100 × share of 3+ syllable words) | Years of schooling |
| Coleman-Liau | 0.0588 × letters per 100 words − 0.296 × sentences per 100 words − 15.8 | U.S. school grade |
| Automated Readability Index | 4.71 × characters per word + 0.5 × words per sentence − 21.43 | U.S. school grade |
Paste at least a few sentences; the results list each score, the Reading Ease band (90 and up very easy, 60 to 70 plain English, below 30 very difficult), an average of the four grade scores, and the word, sentence and syllable counts behind them.
The default text has 70 words in 6 sentences, 11.67 words per sentence, and 95 syllables by the calculator’s count, 1.357 per word. Flesch-Kincaid grade = 0.39 × 11.67 + 11.8 × 1.357 − 15.59 = 5.0. Reading Ease = 206.835 − 1.015 × 11.67 − 84.6 × 1.357 = 80.2, in the “easy” band. Three words have three or more syllables, so the Fog index is 0.4 × (11.67 + 100 × 3 ÷ 70) = 6.4.
| Text | Words per sentence | Syllables per word | Reading Ease | FK grade | Fog |
|---|---|---|---|---|---|
| Calculator sample (6 sentences) | 11.7 | 1.36 | 80.2 | 5.0 | 6.4 |
| Same words joined into 2 sentences with semicolons | 35.0 | 1.36 | 56.5 | 14.1 | 15.7 |
| Children’s text: “Sam has a red ball. He likes to throw it. The dog runs to get it. Then they play again.” | 5.0 | 1.05 | 112.9 | -1.2 | 2.0 |
| Academic sentence: “Statistical significance, conventionally determined through comparison of the calculated probability with a predetermined threshold, provides insufficient information regarding the practical importance of an observed difference.” | 25.0 | 2.64 | -41.9 | 25.3 | 32.4 |
Joining the sample into two sentences changes no words but adds 9.1 grade levels. The scales are not bounded: the children’s text scores above 100 for ease and below grade 0, and the academic sentence, one long sentence of long words, falls below zero for ease.
Rudolf Flesch published the Reading Ease formula in 1948. J. Peter Kincaid and colleagues recalculated it as a grade level in February 1975 for the U.S. Navy, testing 531 enlisted personnel on technical training material; the same report also recalculated the ARI and Fog formulas, but this calculator uses the original ARI and Gunning Fog versions most tools report. Coleman and Liau designed their 1975 formula around letter counts so a machine could score text without counting syllables. Because the grade-level formulas were fit to adult readers, they are rough guides for school texts. A 2021 review of 2,585 patient education materials compared them with the American Medical Association’s recommended sixth-grade level and the National Institutes of Health’s eighth-grade level; only 2.1% and 8.2% met them.
Expecting the same score as Word. Every tool counts syllables and sentence breaks its own way, so scores can differ by a grade or more on the same text. Compare drafts in one tool.
Pasting bullet lists or headings. Lines without end punctuation run together into one long “sentence” and inflate the grade. Add periods or score the prose separately.
Scoring a few lines. Two or three sentences give unstable results; a few paragraphs average out the odd long sentence.
Treating the score as quality. The formulas measure sentence and word length only. Short, choppy text can score well and still be confusing, and a technical term the reader needs may raise the grade for a good reason.
Abbreviations and numbers. “Dr.” or “3.5” followed by a space can be read as a sentence end, and numerals count as one-syllable words.