space4.dev
70+ free developer tools that run entirely in your browser
6 followers
70+ free developer tools that run entirely in your browser
6 followers
Format JSON, encode Base64, decode JWT, convert timestamps, parse cron expressions and more — 70+ free developer tools that run instantly in your browser. No signup, 100% private.
Free
Launch Team
Render: Get up to $100K in startup creditsThe fastest way to deploy and scale apps and agents
Promoted
Hey Product Hunt 👋
I built space4.dev because I kept bouncing between a dozen different tool sites just to format some JSON, decode a JWT, or convert a timestamp — and most of them were slow, cluttered with ads, or asked me to sign up for something that should take 5 seconds.
So I built the tool I actually wanted: 70+ free developer tools — JSON formatting/validation/conversion, Base64/URL/HTML encoding, JWT decoding, Unix timestamps, cron expressions, OpenAPI viewing/validation, and more — all running 100% client-side in your browser. Nothing you paste ever touches a server. No signup, no ads blocking the tool, no data collection.
[Optional: add a specific personal trigger here if there is one — e.g. "This started as an internal tool at [Shreeji Softech] because our own team was tired of X" or "I ran into this constantly working on API integrations and just decided to fix it for good."]
A few things I focused on:
Every tool is its own clean page (no giant kitchen-sink UI)
Fast — no loading spinners, no server round-trips
Genuinely private — your JSON/JWTs/API responses never leave your device
This is a fresh launch (literally days old), so it's very much still growing — more tools, more categories, and refinements are coming based on what people actually need. If you try it and something's missing, broken, or could be better, I'd genuinely love to hear it in the comments. Feature requests especially welcome — this list of tools is going to keep growing based on what devs actually ask for.
Thanks for checking it out! 🙏
love that there's no signup and everything runs locally, super handy. one thing that would make it even better is adding a dark mode toggle in the header so the tools are easier on the eyes during late night debugging sessions
@ceydaeksoz Thank you for your genuine feedback. We have introduced the dark mode now!
Please check and enjoy the day-to-day work with space4.dev!🚀