The W3C Markup Validation Service

Validate by URI

Validate a document online:

Address:

Character Encoding		Only if missing
Document Type		Only if missing
List Messages Sequentially Group Error Messages by Type
Show Source	Clean up Markup with HTML-Tidy
Show Outline	Validate error pages	Verbose Output

Validate by File Upload

Upload a document for validation:

File:

More Options

Character Encoding		Only if missing
Document Type		Only if missing
List Messages Sequentially Group Error Messages by Type
Show Source	Clean up Markup with HTML-Tidy
Show Outline	Validate error pages	Verbose Output

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.