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 “” for attribute “(width|height)” on element “img”: The empty string is not a valid non-negative integer.

The attributes width and height of <img> elements expect a non-negative integer, so an empty string is not allowed. Either define the correct dimension, or remove this attribute.

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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.