Doctype Checker
What is a Doctype?
The doctype declaration must be the first line of your HTML. It tells the browser which version of HTML you are using, ensuring the page renders in standards mode rather than quirks mode.
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Detect outdated HTML tags that should be replaced with modern, standards-compliant alternatives.
Get the HTML lang attribute from any webpage to verify the declared language for accessibility and SEO.
Check if a webpage declares its character encoding, preventing text rendering issues across browsers.
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Check if a webpage is set to noindex, preventing it from appearing in search engine results.
Check the total size of a web page, including all resources, for performance analysis and optimization.
Analyze the ratio of visible text to HTML code. A healthy ratio is important for SEO and page performance.
Check if images on a webpage use the loading="lazy" attribute for improved page speed and performance.