Deprecated HTML tags checker

Free Deprecated HTML Tags Checker — Find Obsolete Markup

This tool scans a page for HTML tags that are deprecated — elements that browsers still tolerate but that have been removed from the modern HTML standard. Enter any URL and you'll see which outdated tags are in use and which modern alternatives should replace them.

Deprecated tags like <font>, <center>, <marquee> and <blink> are relics of an older web. They often still render today, but relying on them is risky: browser support can be dropped at any time, they mix presentation into markup (which belongs in CSS), and they're a sign of aging code that's harder to maintain and may not behave consistently across devices. Clean, standards-compliant HTML is more robust, more accessible, and easier for both browsers and crawlers to parse reliably.

Use this tool to audit older pages or inherited templates for obsolete markup, to clean up code before a redesign, and to confirm a site meets modern HTML5 standards. The fix is usually straightforward — replace presentational tags with CSS, and swap obsolete elements for their semantic equivalents. While deprecated tags rarely cause a direct ranking penalty, modernizing them improves maintainability, consistency and the overall technical quality of your site.

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