I Built a Free Dev Toolbox That Runs 100% in Your Browser

We've all done it. You're debugging a production issue at 2am. You have a JWT token you need to decode right now . So you Google "JWT decoder online", click the first result, and paste your token into some random website. That token contains your user's data. Their email. Maybe their role. Maybe their ID. And you just handed it to a server you know nothing about. The Problem Most online developer tools are built to collect data. Every time you paste a JWT, JSON payload, or API response into one of these sites — that data hits their server. It gets logged. Maybe stored. Maybe sold. As developers we know better. But we do it anyway because it's convenient. What I Built I built dev-tools.run — a collection of 13 developer tools that run entirely in your browser. No server. No database. No logging. No tracking. Your data never leaves your device. Ever. Tools Included Data & Encoding ✅ JSON Formatter & Validator ✅ Base64 Encoder / Decoder ✅ URL Encoder / Decoder ✅ Markdown Preview Auth & To