Free Online Developer Tools

19 dev tools, zero server processing. JSON, Base64—free.

Developer tools Product Hunt Launched Jul 26, 2026 by lixy li_5408 View original post ↗

DevToolCore is a no-frills collection of 19 browser-based utilities that developers actually use daily. JSON formatter with collapsible tree view, real-time regex tester, Base64/URL encoder-decoder, JWT decoder, UUID generator, timestamp converter, and SEO meta tag analyzer — all running client-side so your data never touches a server. No account, no paywall, no annoying popups. Just open the tab and get stuff done. Built with Spring Boot + Alpine.js.

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