wappalyzer

All-in-one Toolbox for Developers

RegExr: Learn, Build, & Test RegEx 好用的正则工具

W3Cschool 提供的工具库，包含各种语言在线 IDE、编码转换、CSS 在线工具等

可以在线看代码流程的网站：loupe

Debuggex: Online visual regex tester. JavaScript, Python, and PCRE.

Tailwind Generator - Collection of useful tools and generators for Tailwind to create, design and customize all kind of web components using a graphical editor.