Readability Checker

How to use Readability Checker

1. Open Readability Checker — it runs entirely in your browser with no setup.
2. Paste or type your input into the text area, or upload a file where supported.
3. Set any options you need. The result appears in the output panel — there is no upload step and no waiting on a server.
4. Review the output instantly; large inputs are handled locally without lag.
5. Copy the result to your clipboard or download it. Your data never leaves the page.

Why use Readability Checker?

• 100% free with no limits, no sign-up and no watermarks.
• Private by design — your data are processed in your browser and never uploaded to a server.
• Fast and lightweight, with instant results even on a phone or a slow connection.
• Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
• Part of a full text tools suite, so related readability checker tasks are one click away.

What people use Readability Checker for

• Checking whether content suits its intended audience.
• Meeting a plain-language requirement for public-sector or medical content.
• Simplifying dense writing before publication.

Readability Checker: limits and things worth knowing

• Flesch Reading Ease runs 0-100, with higher meaning easier. 60-70 is plain English suited to most general audiences; below 30 is genuinely difficult.
• The formulas count syllables and sentence length, nothing more. They cannot detect jargon, ambiguity, poor structure or whether the text makes sense — a paragraph of random short words scores excellently.
• Many public-sector and healthcare guidelines target a reading age around 12, which is roughly Flesch 60-70 or grade level 8.
• Use the score as a prompt to check long sentences, not as a target to optimise. Writing to the metric produces choppy prose.

Is it private and secure?

Your privacy is built in. Readability Checker runs completely on your device, so whatever you enter stays in your browser and is never transmitted, logged or stored on any server.

Network activity: none. Nothing is sent and nothing is fetched. This tool makes no network request at all once the page has loaded — which is why it keeps working if your connection drops.

You do not have to take that on trust — our privacy proof page publishes the Content-Security-Policy that enforces it, lists every third party it permits, and shows how to verify the whole claim yourself.

Learn more

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