About DevBench
DevBench is a free, browser-based toolkit built for developers, DevOps engineers, data teams, and anyone who works with code and data every day. It brings together 130+ carefully crafted utilities — from JSON formatting and Base64 encoding to PDF tools, finance calculators, and regex testing — in one place, with no account required and nothing uploaded to a server.
Why we built it
Every developer knows the feeling: you need to quickly decode a JWT, prettify some JSON, or convert a Unix timestamp — and you end up bouncing between browser tabs, sketchy websites with intrusive ads, or spinning up a local REPL just for a 10-second task. DevBench was built to fix that. One URL, all the tools, no friction.
We also cared deeply about privacy from day one. Most online tools silently send your input to a backend server. When you paste an API key, a JWT, or a customer's data into one of those tools, you are sharing it with a third party. DevBench processes everything locally using your browser's JavaScript engine, Web Crypto API, and Web Workers. Open DevTools, go to the Network tab, and you will see no outbound request when you format JSON, encode text, or run a hash — because there isn't one.
What's inside
DevBench organises its tools into focused categories so you can find what you need quickly:
- JSON & Data — formatter, validator, diff, JSON↔YAML, JSON↔CSV, JSON↔TypeScript, XML tools
- Encoding & Decoding — Base64, URL encoding, HTML entities, hex, binary, ROT13, Morse code, AES-256 encryption
- Text Utilities — regex tester, case converter, diff checker, word counter, Markdown preview, string inspector, Unicode checker
- Developer Tools — JWT debugger, hash generator, UUID/ULID/Nano ID, cron editor, API tester, webhook simulator, AWS Lambda sandbox, colour converter, SQL formatter
- PDF Tools — merge, split, rotate, compress, watermark, page editor, image-to-PDF, PDF-to-JPG
- Image Tools — background remover, image resizer, image merger, compressor, format converter, SVG optimizer, EXIF viewer
- Math & Science — graph calculator, quadratic solver, Pythagorean theorem, GCD & LCM, astronomy tools
- Finance & Health — compound interest, EMI calculator, GST/VAT, BMI, BMR, TDEE, body fat estimator
- Date & Time — Unix timestamp converter, date calculator, age calculator, countdown, timezone converter, world clock
- Conversion — temperature, units, bytes, Roman numerals, number-to-words, aspect ratio, currency, percentage
How it works
Every tool in DevBench runs in your browser. When you paste text, upload a file, or type into a form, the computation happens locally using JavaScript APIs that ship with every modern browser — the Web Crypto API for hashing and encryption, the File API for PDFs and images, Web Workers for CPU-intensive tasks like background removal and Pyodide (Python in the browser) for the code playground.
The only exceptions are requests you explicitly initiate: the API Tester sends HTTP requests through a CORS proxy so you can reach external endpoints, and the Webhook Simulator lets you fire test payloads to URLs you specify. Everything else stays on your device.
Who uses DevBench
DevBench is used by backend engineers formatting API responses, frontend developers debugging tokens and encodings, DevOps teams decoding logs and writing cron schedules, security researchers validating hashes, data analysts cleaning CSVs, students learning about algorithms, and anyone who just needs a quick converter without installing software.
The blog
Beyond the tools, DevBench publishes in-depth technical guides covering topics like JWT security, Base64 encoding internals, regex patterns, Unix timestamps, SHA-256 vs MD5, and more. The blog aims to explain not just how to use each tool, but why the underlying technology works the way it does.
Get in touch
Have a bug to report, a tool suggestion, or just want to say hello? Use the contact form — we read every message. If you spot something broken or have an idea for a new utility, we genuinely want to hear it.