HTML Checking for Large Sites

Rocket Validator automatically scans your sites for accessibility issues using the W3C Validator, hosted on our own servers and integrated into our web crawler.

When was the last time you validated your whole site?

Keep your sites healthy checking for A11Y/HTML issues on an automated schedule.

Saw “<?”. Probable cause: Attempt to use an XML processing instruction in HTML. (XML processing instructions are not supported in HTML.)

A tag starting with <? has been found within the document, but it’s not supported. Probable causes can be:

  • Copy-pasting the contents of an SVG file. If you do that, you should only paste the <svg>...</svg> part, but not the first line with <?xml...>.
  • Unprocessed <?...> tags on server scripting languages like PHP, like <?php>

Learn more:

50,000 Accessibility and HTML checks per month. Fully automated.

Let our automated scanner check your large sites using Axe Core and W3C Validator.