Readability Score Calculator
Measure how easy your writing is to read with Flesch Reading Ease and Flesch–Kincaid Grade Level scores.
About the Readability Score Calculator
The Readability Score Calculator tells you how easy your writing is to read. Paste any text — an essay, a blog post, an email, or a product description — and it instantly reports two of the most widely used readability measures: the Flesch Reading Ease score and the Flesch–Kincaid Grade Level. Alongside the scores you get the underlying counts, so you can see exactly what's driving your result: total words, total sentences, average words per sentence, and average syllables per word.
This tool is for writers, students, teachers, editors, and anyone who wants their message to land clearly with its audience. Long sentences and multi-syllable words push readability down; shorter sentences and plainer words push it up. Watching the scores change as you edit makes it easy to aim for a target reading level. Everything runs entirely in your browser — nothing you paste is uploaded, there's no sign-up, and the calculator keeps working even without an internet connection. Your draft never leaves your device.
How to use
- Paste or type your text into the box. Scores update live as you type, so there's no button to press.
- Read the Flesch Reading Ease score. Higher is easier — 60–70 is plain English understood by 13–15 year-olds, while lower scores signal denser, more academic writing.
- Read the Flesch–Kincaid Grade Level. This estimates the U.S. school grade a reader needs to follow your text; a grade of 8 means an average eighth-grader should understand it.
- Check the raw counts below the scores to see whether long sentences or long words are affecting your result, then edit and watch the numbers respond.
How the scores are calculated
Flesch Reading Ease uses the formula 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words). Flesch–Kincaid Grade Level uses 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59. Both depend on average sentence length and average syllable count, which is why shortening sentences and choosing simpler words improves your scores. Syllables are estimated by counting vowel groups in each word and removing a silent trailing "e", so the count is a close approximation rather than a dictionary lookup.
Frequently asked questions
What is a good Flesch Reading Ease score?
For most general audiences, aim for 60 or above, which corresponds to plain, easily understood English. Marketing copy and news writing often target 60–70, while technical or academic material naturally scores lower.
What does the Flesch–Kincaid Grade Level mean?
It maps your text to a U.S. school grade. A grade level of 8 means an average eighth-grade student should be able to read it, and many editors recommend writing for a general audience at grade 8 or below.
How accurate is the syllable count?
Syllables are estimated with a vowel-group heuristic that counts runs of vowels and drops a silent final "e". This is fast and works well for most English text, but unusual spellings and proper nouns can be off by a syllable, so treat the scores as close guides rather than exact figures.
What happens if I clear the box or paste only spaces?
You simply get a friendly prompt to add some text — never a "NaN" or an error. Scores appear only once there is at least one real word to measure.
Is my text private, and does this work offline?
Yes on both counts. All the analysis happens locally in your browser; nothing you paste is sent to a server, stored, or tracked. Once the page has loaded, the calculator continues to work with no internet connection.