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HTML Guide

Free site validation

Find out what web pages on your sites are affected by HTML issues.

Almost standards mode doctype. Expected “<!DOCTYPE html>”.

Rocket Validator checks HTML on your sites using the latest version of W3C Validator Nu HTML Checker, which is intended for HTML5 documents.

The page scanned is using an “almost standards mode” doctype, instead of the expected <!DOCTYPE html>. While the almost standards mode was used in the transition to HTML5, you should consider moving to the HTML5 standard.

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