Runs 100% in your browser
Your data never leaves your device. zero uploads.
Encode JWT header and payload data in a local workspace for development and inspection.
Create a token-shaped test value from editable JSON sections. Review each claim and the algorithm header before copying the result into a development fixture. Use a real authentication system for production token issuance.
Edit a sample payload to include a test subject and inspect how its encoded token changes.
This utility does not replace trusted token issuance or key management. Inspect the workspace's signing behavior before relying on a generated value; encoding alone provides no authenticity.
Paste a token to decode it, or edit the header and payload for encoding. Review the JSON values and choose the relevant action. Copy the output and verify its intended use in your own environment.
This utility does not replace trusted token issuance or key management. Inspect the workspace's signing behavior before relying on a generated value; encoding alone provides no authenticity.
No registration, no tracking of your content, no server uploads. Don't just take our word for it:
Your files and text are processed entirely on your device. Nothing is ever sent to us.
Once loaded, this tool keeps working with your Wi-Fi turned off. Try it.
Open your browser's DevTools → Network tab. You'll see zero requests carrying your data.
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