- Validate by URI
- Validate by File Upload
- Validate by Direct Input

Validate by URI

Validate a document online:

Address:

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Validate by File Upload

Upload a document for validation:

File:

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Note: file upload may not work with Internet Explorer on some versions of Windows XP Service Pack 2, see our information page on the W3C QA Website.

Validate by direct input

Enter the Markup (Full Document) to validate:

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