The HTML5 Test, at, is a website that enables you to validate how well today’s web browsers support the most current HTML5 specification. As mentioned, HTML5 is the “living standard,” so the official specifications of today may differ tomorrow. Because WHATWG wants HTML5 to evolve over time, you can count on the HTML5 Test to verify sites using the latest specifications available.

The HTML5 Test is not designed to be an all-inclusive verifier of every HTML5 feature. It quantifies HTML5 support at a high level and provides you with the ability to compare different web browsers side by side. It works by identifying when a tested feature is supported by your browser, but it does not validate ...

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