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Readability Score Checker

Score your writing with five readability formulas and see the reading age each one implies.

Scored live as you type. Nothing leaves your browser.

Readability scores

Paste some prose above to see how hard it is to read.

How to check the readability of your writing

  1. Paste your text

    Drop an article, email, or page of copy into the box. The scores appear on their own a moment after you stop typing.

  2. Read the interpretations

    Each formula is shown with a plain English line saying which reading age it corresponds to, so you never have to look a number up.

  3. Edit and watch it move

    Shorten long sentences and swap long words for short ones, then press Copy report to save the numbers alongside the draft.

Why use this tool

Five formulas at once

Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, SMOG, and Coleman-Liau are all calculated from the same sample, so you can see whether they agree.

Plain English interpretations

Every score carries a sentence explaining what it means, such as easily understood by 13 to 15 year olds, rather than leaving you with a bare number.

The stats behind the score

Sentences, words, syllables, words per sentence, syllables per word, and the count of long words are all shown, so you can see which input is driving the result.

Warns on short samples

Under about 100 words or 4 sentences the averages swing wildly. The tool says so instead of presenting an unreliable score as fact.

Nothing leaves your browser

Scoring happens on your device. The text is never uploaded, stored, or logged, and the tool is free with no signup.

About this tool

This readability checker measures how much effort your writing asks of a reader. It splits the text into sentences and words, estimates the syllables in each word, and feeds those counts into five long-established formulas. Flesch Reading Ease returns a 0 to 100 score where higher is easier. Flesch-Kincaid Grade, Gunning Fog, SMOG, and Coleman-Liau each return a US school grade level, and the tool averages those four into one headline figure so you have a single number to aim at.

Every formula rewards the same two things: shorter sentences and shorter words. Flesch Reading Ease and Flesch-Kincaid work from average sentence length and average syllables per word. Gunning Fog and SMOG focus on words of three or more syllables. Coleman-Liau ignores syllables entirely and works from letters and sentences per hundred words, which makes it a useful second opinion when the syllable estimate is doing something strange. Syllables come from a vowel-group estimate: runs of vowels count as one syllable each, a silent trailing e is dropped, and digits are voiced separately so a year or a price is not scored as a single silent beat.

Aim for grade 8 or below for general audiences, grade 6 for anything that must be understood under pressure, and treat anything above grade 14 as a signal to break sentences up. The scores are estimates rather than measurements: they know nothing about jargon, structure, or whether a sentence makes sense, so a short sample of nonsense can still score well. Everything runs in your browser, so drafts stay private, and the tool is free with no signup. For raw totals and reading time, use the word counter; to strip stray characters out of a pasted draft first, use the text cleaner; and to check which phrases you are repeating, use the keyword density checker.

Frequently asked questions

What is a good readability score?
For general audiences aim for a Flesch Reading Ease of 60 or above, which is roughly grade 8 and readable by most adults without effort. Plain language guidance for public information often targets grade 6. Technical documentation for specialists commonly sits between grade 10 and 14.
Why do the five formulas disagree?
They weight different things. Gunning Fog and SMOG punish words of three or more syllables heavily, Coleman-Liau ignores syllables and counts letters instead, and the Flesch formulas balance sentence length against syllables per word. A gap of two or three grades between them is normal. The headline figure averages the four grade level formulas so one outlier does not dominate.
How are syllables counted?
With a vowel-group estimate: each run of vowels in a word counts as one syllable, a silent trailing e is dropped, and every word with letters scores at least one. Digits are counted separately so numbers are not treated as silent. It is an estimate, so unusual spellings and names can be off by a syllable.
How much text do I need?
About 100 words across at least 4 sentences. Below that the tool shows a warning, because the formulas average sentence length and a single long sentence can move the result by several grades. SMOG in particular was designed around samples of 30 sentences.
Is my text uploaded anywhere?
No. Scoring happens entirely in your browser. Your text never leaves your device and is not stored or logged, so it is safe for unpublished drafts and confidential documents.

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