The W3C CSS Validation Service

By URI
By file upload
By direct input

Validate by URI

Enter the URI of a document (HTML with CSS or CSS only) you would like validated:

Address:

More Options

Profile:		Medium:
Warnings:		Vendor Extensions:

Validate by file upload

Choose the document you would like validated:

Local CSS file:

More Options

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Warnings:		Vendor Extensions:

Validate by direct input

Enter the CSS you would like validated:

More Options

Profile:		Medium:
Type:		Warnings:		Vendor Extensions:

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Note: If you want to validate your CSS style sheet embedded in an (X)HTML document, you should first check that the (X)HTML you use is valid.