JWT debugger
Decode header + payload + signature, and verify HS256/384/512 signatures.
Also known as: JWT debugger, JSON Web Token decoder, JWT verifier.
100% offline · macOS, Windows & Linux · free for personal use
// overview
What it does
JWT debugger is one of 55 tools in Hexkit, a desktop developer toolbox that runs entirely on your own machine. Decode header + payload + signature, and verify HS256/384/512 signatures.
Because Hexkit is a native app rather than a web page, anything you paste into the jwt debugger stays local — there are no uploads, no accounts and no telemetry. You can decode tokens and inspect encoded data even with the network turned off, which makes it safe for tokens, keys and production data.
// steps
How to use JWT debugger
- 1
Open Hexkit and select "JWT debugger", or press the command-palette key and start typing its name.
- 2
Paste the text or token you want to encode or decode. Decode header + payload + signature, and verify HS256/384/512 signatures.
- 3
Read or copy the result. Everything is computed locally by Hexkit's Rust core, so nothing is ever uploaded.
Tip: the command palette opens any tool in one keystroke.
// faq
Frequently asked questions
- Is JWT debugger free?
- Yes. JWT debugger is part of Hexkit, which is free for personal and non-commercial use on macOS, Windows and Linux.
- Does JWT debugger work offline?
- Completely. Hexkit runs every tool locally with no network access, so JWT debugger works on a plane or an air-gapped machine.
- Is my data uploaded anywhere?
- No. Hexkit makes no network calls and has no telemetry — whatever you paste stays on your computer.
- Is it safe to decode a production JWT here?
- Yes. Unlike web-based JWT debuggers, Hexkit runs locally and makes zero network calls, so an access token you paste never leaves your machine.
- Can it verify the signature?
- It decodes any JWT and verifies HMAC signatures (HS256, HS384, HS512) against a secret you provide. Decoding never requires the secret.
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Related tools
Use JWT debugger without sending your data anywhere.
JWT debugger ships inside Hexkit — a free, offline developer toolbox for macOS, Windows and Linux. No account, no uploads.