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.

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Attribute “isolang” not allowed on element “html” at this point.

Instead of using the isolang attribute to define the language of the document, you can use lang with an ISO 639-1 two character code.

For example, for Portuguese:

<html lang="pt">

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