Readability Checker
Score your text with Flesch Reading Ease and Flesch-Kincaid Grade, and see what is making it hard to read.
How to use this tool
- Paste or type your text into the box above.
- The result updates as you change the input — there is nothing to submit and nothing to wait for.
- Read the figures in the result panel, or copy the converted text.
- Use Copy or Download if you need the output elsewhere. Nothing was uploaded at any point.
These are the two standard readability formulas, used by US plain-language rules and built into most word processors. They measure sentence length and syllable count — not whether the writing is good, but they reliably catch prose denser than it needs to be.
Readability Checker — the specification
| Flesch Reading Ease | 0–100. Higher is easier. 60–70 is plain English |
|---|---|
| Flesch-Kincaid Grade | US school grade level needed to read it comfortably |
| Long sentences | Flags anything over 25 words |
| Passive voice | Estimates passive constructions |
| Wordy phrases | Flags common padding with shorter replacements |
How it works
This tool runs entirely in your browser. There is no server involved, which means nothing you type or upload is transmitted, stored, or logged — and there are no usage limits, because there is nothing for us to ration.
You can confirm it yourself: open your browser's developer tools, select the Network tab, and use the tool. No request is made.
A worked example
Run against this page’s own code, with the real input and the real output reproduced below.
What went in
The photograph must be a recent colour image with a plain white background. It should be between twenty and fifty kilobytes in size. Files outside that range are rejected by the portal automatically, without review, and the candidate is not told which rule was broken.
What came back
| Flesch Reading Ease | 58.1 |
|---|---|
| th gradeFlesch-Kincaid Grade | 8.9 |
| Words | 45 |
| Sentences | 3 |
| Average sentence length | 15.0 |
| wordsAverage syllables per word | 1.58 |
| Sentences over | 25 |
| words | 0 |
| Possible passive constructions | 3 |
Everything above happened in the page as the text was typed. Nothing was sent to a server, which is why it works offline once the page has loaded and why there is no limit on how often you use it.
Who needs Readability Checker
Writers aiming at a general audience, anyone producing public-facing documentation, and content teams checking a page is not harder than it needs to be.
Readability Checker — frequently asked questions
What score should I aim for?
For a general audience, Flesch Reading Ease of 60–70 — roughly 8th to 9th grade. Journalism typically lands around 60. Technical documentation sits lower and that is often appropriate; the score is a check, not a target to game.
How is the score calculated?
Flesch Reading Ease = 206.835 − 1.015 × (words per sentence) − 84.6 × (syllables per word). Only two things move it: sentence length and word length. Splitting long sentences is by far the fastest improvement.
Is a low score bad?
Not necessarily. A legal contract or research paper scores low because the vocabulary genuinely requires it. The score is useful when your text is harder than your audience needs, not as an absolute standard.
How accurate is the passive voice count?
It is an estimate from a pattern match, so it over-counts slightly — phrases like "is finished" get flagged. Treat it as a prompt to look, not a definitive count.
Does this work offline?
Yes. Once the page has loaded you can disconnect from the internet and it keeps working, because all the processing happens in your browser. That is also the simplest way to confirm nothing is being sent anywhere.
Is there a limit on how much I can paste in?
Nothing we impose. The practical limit is your device’s memory, since the work happens locally. Very large inputs get slower rather than being refused.
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Background reading: Text and Developer Tools That Never Upload Your Data
Your file never leaves your device. Open your browser's Network tab while you use this page and you will see no upload — how that works.
Disclaimer. Published requirements change without notice. Confirm against the official source before you submit. Full disclaimer.