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W3C Validation

The W3C validation badge performs validation of the HTML, SVG, MathML, ITS, RDFa Lite, XHTML documents. The badge uses the type property of each message found in the messages from the validation results to determine to be an error or warning. The rules are as follows:

  • info: These messages are counted as warnings
  • error: These messages are counted as errors
  • non-document-error: These messages are counted as errors

This badge relies on the https://validator.nu/ service to perform the validation. Please refer to https://about.validator.nu/ for the full documentation and Terms of service.

Path Parameters
parser string — REQUIRED

Possible values: [default, html, xml, xmldtd]

The parser that is used for validation. This is a passthru value to the service

  • default: This will not pass a parser to the API and make the API choose the parser based on the validated content
  • html: HTML
  • xml: XML (don't load external entities)
  • xmldtd: XML (load external entities)

Example: html

Query Parameters
targetUrl string — REQUIRED

URL of the document to be validate

Example: https://validator.nu/

preset string

Possible values: [HTML, SVG 1.1, MathML 3.0, HTML, SVG 1.1, MathML 3.0, ITS 2.0, HTML, SVG 1.1, MathML 3.0, RDFa Lite 1.1, HTML 4.01 Strict, URL / XHTML 1.0 Strict, URL, HTML 4.01 Transitional, URL / XHTML 1.0 Transitional, URL, HTML 4.01 Frameset, URL / XHTML 1.0 Frameset, URL, XHTML, SVG 1.1, MathML 3.0, XHTML, SVG 1.1, MathML 3.0, RDFa Lite 1.1, XHTML 1.0 Strict, URL, Ruby, SVG 1.1, MathML 3.0, SVG 1.1, URL, XHTML, MathML 3.0]

This is used to determine the schema for the document to be valdiated against.

Example: HTML, SVG 1.1, MathML 3.0

style string

Possible values: [flat, flat-square, plastic, for-the-badge, social]

If not specified, the default style for this badge is "flat".

Example: flat

logo string

Icon slug from simple-icons. You can click the icon title on simple-icons to copy the slug or they can be found in the slugs.md file in the simple-icons repository. Further info.

Example: appveyor

logoColor string

The color of the logo (hex, rgb, rgba, hsl, hsla and css named colors supported). Supported for simple-icons logos but not for custom logos.

Example: violet

logoSize string

Make icons adaptively resize by setting auto. Useful for some wider logos like amd and amg. Supported for simple-icons logos but not for custom logos.

Example: auto

label string

Override the default left-hand-side text (URL-Encoding needed for spaces or special characters!)

Example: healthiness

labelColor string

Background color of the left part (hex, rgb, rgba, hsl, hsla and css named colors supported).

Example: abcdef

color string

Background color of the right part (hex, rgb, rgba, hsl, hsla and css named colors supported).

Example: fedcba

cacheSeconds string

HTTP cache lifetime (rules are applied to infer a default value on a per-badge basis, any values specified below the default will be ignored).

Example: 3600

link string[]

Specify what clicking on the left/right of a badge should do. Note that this only works when integrating your badge in an <object> HTML tag, but not an <img> tag or a markup language.