Updated November 2026 · free, works in your browser
Show the formulas
Grade level = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59
Reading ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)
Syllables are estimated with a rule-based counter for English, so results can differ slightly between tools. Grades below 0 are shown as 0 and ease scores are kept between 0 and 100.
A reading level calculator shows how difficult a text is by looking at sentence length and word length. Paste your text above and you get the Flesch-Kincaid grade level (the US school grade needed to understand it) and the Flesch Reading Ease score, from 0 (very hard) to 100 (very easy).
How to use
- Paste or type your text into the box. A paragraph of 100 words or more gives the most reliable result.
- Read the grade level and the reading ease score, which update as you type.
- Open the full version to see word, sentence and syllable counts and the approximate reader age.
- Shorten long sentences or swap long words for simpler ones, then watch the score change.
- Copy a link to share the exact text and result with a colleague or a class.
How it is calculated
Both scores come from the Flesch formulas, developed by Rudolf Flesch and adapted by J. Peter Kincaid for US Navy training material.
Grade level = 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59
Reading ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)
- Words ÷ sentences is the average sentence length.
- Syllables ÷ words is the average word length in syllables.
- The grade level is a US school grade. Add about five to get a typical reader age.
Syllables are counted automatically with simple English spelling rules, so a few words may be miscounted. The tool shows grades below 0 as 0 and keeps the ease score between 0 and 100.
Flesch Reading Ease scale
| Score | Difficulty |
|---|---|
| 90–100 | Very easy |
| 80–90 | Easy |
| 70–80 | Fairly easy |
| 60–70 | Standard (plain English) |
| 50–60 | Fairly difficult |
| 30–50 | Difficult |
| 0–30 | Very difficult |
Frequently asked questions
What is a good reading level for general readers?
Many writing guides suggest a reading ease score of about 60 to 70, which is roughly a grade 7 to 8 level. Technical or academic writing often scores lower.
What is the difference between grade level and reading ease?
They use the same two inputs, sentence length and syllables per word, but present them differently. Grade level is a school year, where a higher number means harder text. Reading ease is a score, where a higher number means easier text.
Does it work for languages other than English?
No. The constants and the syllable counting are made for English. Results for other languages are not meaningful.
Why do short texts give odd scores?
With only a sentence or two, one long word or one long sentence changes the averages a lot. Test at least a full paragraph.
Does the score measure quality or understanding?
No. It only measures sentence and word length. It cannot judge vocabulary difficulty, topic familiarity, layout or how well the ideas are explained, so use it as a guide and not as a verdict.
From reading levels to the road
The same habit of matching books to the reader helps when you pack for a family trip. Check a few books or travel guides for each child, mix easy favourites with slightly harder ones, and choose titles that suit long train rides, flights or quiet evenings in your accommodation. When you compare places to stay, a quiet corner or a comfortable reading spot in the room can make downtime easier for everyone.
Other tools
- Citation GeneratorTurn book or website details into a formatted APA, MLA or Chicago reference and in-text citation.
- CRAAP Test Source Evaluation ChecklistRate a website or article on currency, relevance, authority, accuracy and purpose and get an instant credibility score.
- Information Literacy Skills ChecklistPick a grade band, tick the information literacy skills already taught and see progress with the gaps highlighted.
This is an independent guide. It is not affiliated with Washington Library Media Association.