Live demo · Tooling
Developer toolkit
Nine tools that never make a network request. Turn off your wi-fi and they all still work.
Errors report the exact character position, not just unexpected token.
Decoded here, in this tab. A JWT is a credential — pasting one into a random website hands somebody your session. This page has nowhere to send it.
Unicode-safe in both directions — plain btoa throws on anything above U+00FF.
Computed by the browser's own implementation — no crypto library is bundled here.
From crypto.getRandomValues, not Math.random.
Runs under a step budget, so a catastrophically backtracking pattern warns instead of freezing the tab.
The argument
Most things built as a service do not need to be one.
Every tool on this page could have been an endpoint. It would have been easier to write, easier to instrument, and it would have quietly collected every JWT, every JSON payload and every string anyone ever hashed.
None of that is necessary. The browser already has a JSON parser, a cryptography implementation and a regular-expression engine. Using them means the privacy claim is not a policy a reader has to trust — it is something they can verify by pulling the network cable.
Got an internal tool that should exist?
The small ones usually pay for themselves in a week.