I'm an engineer from Baku. I build things as a hobby. I got tired of opening 5 different sites every time I needed to check a certificate, calculate subnets, or encrypt something. Each one had ads, wanted my email, and made me wonder where my data went. So I started building. One tool. Then another. 36 tools later — here we are. The unusual part It's a single HTML file. 460KB. No npm. No build step. No server. open index.html Enter fullscreen mode Exit fullscreen mode That's the entire setup. Works offline, works on any machine. What's inside The usual stuff — JSON, JWT, Base64, UUID, QR codes, Regex.…