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.