How to use the readability checker
- Paste your text into the box, or press Sample to try an example.
- Read your Flesch reading ease score and overall reading level at the top.
- Open Score details to compare all six readability formulas.
- Rewrite the sentences listed under Hard-to-read sentences. Scores update as you edit.
What the scores mean
| Flesch reading ease | Difficulty | Typical reader |
|---|---|---|
| 90–100 | Very easy | Age 11 |
| 80–89 | Easy | Age 12 |
| 70–79 | Fairly easy | Age 13 |
| 60–69 | Standard | Ages 13–15 |
| 50–59 | Fairly difficult | Ages 15–18 |
| 30–49 | Difficult | College students |
| 0–29 | Very difficult | University graduates |
The other five formulas give a US school grade level: a score of 8 means a typical 8th-grade student (about 13–14 years old) can understand the text. Most newspapers write at grade 8–10. Government plain-language guidance and most web writing aim for grade 8 or lower.
The six formulas
- Flesch reading ease (1948) uses average sentence length and average syllables per word. Higher is easier.
- Flesch-Kincaid grade level uses the same two measures, scaled to a school grade. It was developed for the US Navy in 1975 and is built into Microsoft Word.
- Gunning Fog index counts the share of "complex" words with three or more syllables.
- SMOG index is based on the number of words with three or more syllables. It is widely used for health information.
- Coleman-Liau index counts letters instead of syllables, so it doesn't depend on syllable rules.
- Automated Readability Index (ARI) also uses characters per word and words per sentence.
Each formula weighs things differently, so their results usually differ by a grade or two. The reading level shown at the top is the average of the five grade-level scores.
How to make your writing easier to read
- Split sentences longer than 25 words into two.
- Swap long words for short ones: "use" instead of "utilize", "help" instead of "facilitate", "about" instead of "approximately".
- Use the active voice: "We fixed the bug" is easier than "The bug was fixed by us".
- Keep one idea per paragraph and use headings and lists to break up long sections.
Read more in our guide How long should a sentence be?
Frequently asked questions
What is a good readability score?
For most websites, blogs and emails, aim for a Flesch reading ease of 60 or higher and a grade level of 8 or lower. Academic and technical writing is naturally harder, often scoring 30–50.
Why is my score different from Microsoft Word or another tool?
Tools count syllables and sentences in slightly different ways. Syllables are estimated with English spelling rules, so a few words are always miscounted. Differences of a few points are normal.
Does it work for languages other than English?
These formulas were designed for English. Scores for other languages are not reliable.
Is my text private?
Yes. All scores are calculated in your browser and your text is never uploaded.