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.

25,000 HTML checks per month. Is that enough for your site?

Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.

Bad value “auto” for attribute “height | weight” on element “img”: Expected a digit but saw “a” instead.

The width and height attributes on <img> elements expect a digit to specify the dimension in pixels. It should not contain units, letters or percent signs.

You can achieve this using CSS instead, for example:

<!-- Invalid syntax, the height attribute expects only digits -->
<img src="photo.jpg" alt="cat" height="auto" />

<!-- Valid syntax using CSS -->
<img src="photo.jpg" alt="cat" style="height: auto"  />

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Related W3C validator issues

25,000 HTML checks per month. Is that enough for your site?

Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.