Keep ZeroServer.tools free, private & ad-free
979+ developer tools that run 100% in your browser — no sign-up, no data uploads, no tracking, and no ads. It's built and maintained by one developer, and kept free for everyone.
Where your support goes
- Hosting & domain. The site runs on a global CDN so it's fast everywhere — that has real monthly costs.
- Staying ad-free. Most free tool sites pay their way with trackers and ads. Tips let this one stay clean and private instead.
- More tools. Every bit of support buys time to build and maintain new tools.
Buy me a coffee
A one-time $3–5 tip on Ko-fi. Ko-fi takes 0% — every cent goes to hosting and keeping the lights on.
Tip on Ko-fi →Star it on GitHub
Stars cost nothing and help other developers discover the project. It's the highest-leverage free thing you can do.
Star on GitHub →Share a tool
Post a tool you found useful on X, Reddit, or your team chat. Word of mouth is what keeps an indie project alive.
Follow & share →Hire me
Need a private, client-side tool built for your team? Commissioning work is the most direct way to support this.
See what I build →Where the money goes
ZeroServer.tools is a static site. Every tool runs in your browser, so there is no application server, no database and no per-request compute cost — which is the main reason 979 tools can be given away rather than metered. What remains is domain registration, the build and hosting of the static export, and the occasional paid API used only to verify a tool against a reference implementation.
The larger cost is time. Most tools here are a day or two of work and a longer tail of corrections afterwards — a colour converter is easy to write and hard to get right at the edges, and the fixes usually come from someone reporting an answer that looked wrong. That reporting is worth more than a tip, and it is free.
Why there is no subscription
A subscription would require accounts, and accounts would require storing something about you. The whole premise of this site is that your data never leaves the machine — a paste into a JSON formatter, a screenshot dropped into an image tool, a password checked for entropy. Adding a login would undermine the one property that makes those uses safe, so the funding model has to be optional rather than gated.
That also means nothing is held back. There is no pro tier, no watermark, no export limit and no feature that appears only after payment. If a tool is here, it is complete.
Free things that help more than money
A bug report with the input that caused it is the single most useful thing anyone sends. Second is a note about a tool that produced a plausible but wrong answer, because those are the failures nobody notices — a checksum that looks fine, a conversion off in the third decimal, a validator accepting something it should reject. Several of the fixes shipped here started as one sentence from a stranger.
Sharing a specific tool with someone who needed it is the other one. Search traffic finds tools people already know to look for; a recommendation is how anyone discovers the ones they did not know existed.
No pressure — every tool here is free forever whether you tip or not. Thank you for using ZeroServer.tools. 💚