About DevConverter
DevConverter is a collection of free developer utilities built with one goal in mind: get the answer quickly, without sending your data anywhere.
Why I built this
Like most developers, I found myself constantly searching for quick conversion tools online — decode this Base64 string, figure out what this Unix timestamp means, check if this JSON is valid. The tools I found were either plastered with ads, required sign-ups, or — most concerning — sent my data to a server I knew nothing about.
Pasting a JWT or a private key into a random website to decode it is not something I was comfortable with. So I built the tools I wanted to use myself. Everything on DevConverter runs locally in your browser using JavaScript — no data ever leaves your machine.
This is a side project. There is no team, no funding, and no roadmap driven by investor priorities. Just a set of tools that I find useful and maintain in my spare time.
Principles
Privacy by design
All tools run entirely in your browser. Sensitive data like JWTs, private keys, and personal text never touch a server.
No account required
Every tool is available immediately, no sign-up, no email, no paywall. Open the page, use the tool, close the tab.
Fast and focused
Each tool does one thing well. No feature bloat, no upsells, no distractions. Real-time output as you type.
Actually free
The site is supported by unobtrusive advertising. The tools will never move behind a subscription or usage limit.
How it’s built
DevConverter is built with Next.js (App Router), TypeScript, and Tailwind CSS. Pages are statically generated at build time, so there is no server-side processing at runtime — the entire site is served as static files from a CDN edge network. This makes it fast to load and means there is literally no server to receive your data.
All conversion logic is implemented using browser-native APIs and carefully chosen open-source libraries where a reliable implementation is more important than DIY code (for example, TOML parsing and SQL formatting). The approach prioritizes correctness and security over minimizing dependencies.
DevConverter currently offers over 60 tools across 10 categories: encoding, format conversion, string manipulation, hashing, number bases, date and time, color, generators, network utilities, and image tools. New tools are added regularly.
Browse all toolsGet in touch
Found a bug? Have a tool request? Something broken? I’d genuinely like to hear it. Reach out at devconverter@proton.me and I will get back to you.