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Word Counter
Counts words, characters, sentences, paragraphs and reading time live as you type, using the…
Readability Checker
Scores text with Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, SMOG, Coleman-Liau and ARI, and explains each score.
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In short
Readability formulas score text on sentence length and word length, and this tool runs six of them: Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, SMOG, Coleman-Liau and the Automated Readability Index. Flesch Reading Ease is the one most people quote, and it runs backwards from the others — a high score means easy. Above 90 is very easy, around fifth-grade level; 60 to 70 is plain English at eighth or ninth grade and the usual target for web writing; 30 to 50 is difficult, university level; below 30 is professional or academic. The grade-level formulas all return a US school year instead, and they will disagree with each other by a year or two on the same text, which is normal and a reason to look at the spread rather than one number. The limitation is fundamental and worth stating plainly: every one of these formulas measures only sentence length and syllable count. A short sentence full of jargon scores beautifully and still reads badly. Use the score to find the paragraphs worth rereading, then read them yourself.
How to use the Readability Checker
- Paste or type your text into the input box, or drop in a .txt file.
- The counts update live as you type — there is no button to press.
- Use the copy or download button to keep the results.
About the Readability Checker
The Readability Checker scores text with Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, SMOG, Coleman-Liau and ARI, and explains each score. It runs as plain JavaScript inside the page, which means there is no upload step, no queue and no size limit imposed by a server — the only limit is your own device.
What people use it for
- Getting web copy down to the grade 8 level most style guides ask for.
- Checking that patient information or legal plain-English rewrites are genuinely simpler.
- Comparing your draft against a competitor page.
Details
| Flesch 90–100 | Very easy — 5th grade |
|---|---|
| Flesch 60–70 | Plain English — 8th to 9th grade, the usual web target |
| Flesch 30–50 | Difficult — university level |
| Flesch 0–30 | Very difficult — professional or academic |
The maths behind it
This tool uses six standard indices. Flesch Reading Ease is 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words); Flesch-Kincaid Grade is 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59. Every intermediate value is shown on screen, so the result can be checked by hand.
Every one of these formulas is a proxy built on sentence length and syllable count. A short sentence full of jargon scores well and still reads badly. Use the number to find problem paragraphs, then read them yourself.
Frequently asked questions
Do I need an account to use the Readability Checker?
No charge and no sign-up. There is no free tier to run out of because there is no paid tier — inputtesthub.com is funded by advertising rather than by metering the utility.
Can you see what I put into this utility?
No. The Readability Checker runs entirely in your browser using JavaScript. Because the work happens locally, the utility also keeps working if your connection drops, and closing the tab is all it takes to discard everything.
Can I check the maths myself?
It uses six standard indices. Flesch Reading Ease is 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words); Flesch-Kincaid Grade is 0.39 × (words ÷ sentences) + 11.8 × (syllables ÷ words) − 15.59. The full working is printed under the result, so you can follow every step rather than trusting a black box.
What do people use the Readability Checker for most?
In practice it gets used for three things: getting web copy down to the grade 8 level most style guides ask for. Checking that patient information or legal plain-English rewrites are genuinely simpler. Comparing your draft against a competitor page. It is built for exactly those cases rather than being a general-purpose tool with this bolted on.
Any caveats I should know about?
Every one of these formulas is a proxy built on sentence length and syllable count. A short sentence full of jargon scores well and still reads badly. Use the number to find problem paragraphs, then read them yourself.
What are the reference figures here?
Flesch 90–100 is Very easy — 5th grade. Flesch 60–70 is Plain English — 8th to 9th grade, the usual web target. Flesch 30–50 is Difficult — university level. These are printed on the page itself, so you do not have to take them on trust.
Can I use the Readability Checker on mobile?
Yes. The page is responsive and the utility works in Chrome, Safari, Firefox, Edge and Samsung Internet on both Android and iOS. There is no app to install and nothing to sign into.
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