HTML Checking for Large Sites
Rocket Validator automatically checks your pages on the W3C Validator.
Bad value X for attribute “srcset” on element “source”: No width specified for image Y. (When the “sizes” attribute is present, all image candidate strings must specify a width.)
The sizes
attribute is used to complement the srcset
attribute on an <img>
tag for responsive images. When this attribute is present, all image candidates must specify its width.
Learn more:
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.