HTML Checking for Large Sites

Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.

The value of the “for” attribute of the “label” element must be the ID of a non-hidden form control.

<label> tags are used to label inputs in form, which need to be present and visible in the document, for example:

<label for="age">Age</label>
<input id="age" />

Related W3C validator issues