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On-page SEO Checker
Check page HTML for title, description, headings, alt text, canonical, Open Graph, structured data and keyword use.
Free, no uploads, no sign-up. Runs 100% in your browser.
How On-page SEO Checker works
Generated in your browser from what you type or drop. Nothing is fetched from or sent to your site. The page source you paste or drop is checked on your device.
Input: HTML. Output: Report.
How to use On-page SEO Checker
- Paste page source or drop an HTML file.
- Add your main keyword.
- Fix the failing checks first.
Tips
- Nothing is fetched from your site, so these tools also work for staging sites and pages behind a login.
- Test changes on a staging copy of your site first.
On-page SEO Checker FAQ
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
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