DexartTools
HTML & CSS Ready to use

HTML5 Compliance Checker

Check markup against modern HTML requirements.

How to use

  1. 1Open the HTML5 Compliance Checker tool page.
  2. 2Enter or paste your input into the provided fields.
  3. 3The tool processes your input instantly in your browser.
  4. 4Copy or download the result using the buttons provided.

Privacy & limitations

  • Processing happens locally in your browser — nothing is uploaded.
  • Works on modern desktop and mobile browsers.
  • Very large inputs may take a moment; the interface will show progress.

Support

Found a bug or want an improvement? We read every report.

Report a problem

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