JWT Decoder
JWT Decoder helps you complete encoding and decoding quickly with instant results in your browser. No upload is required and your data stays on your device.
This tool runs entirely in your browser. Your files and text are never uploaded to our servers.
Your input is processed locally in the browser under normal use.
How to use
- Open JWT Decoder and enter or paste your input.
- Adjust options to match your scenario.
- Copy the result and continue your work.
FAQ
How do I use JWT Decoder?
Enter your input above, review the live result, then copy or reuse the output in your workflow.
Is JWT Decoder safe for sensitive data?
Yes. Processing runs in your browser whenever possible, so content is not sent to a remote server in normal use.
About this tool
JWT Decoder transforms data between encoding schemes used on the web and in APIs. Understanding the underlying character set or binary representation prevents data corruption across systems.
Key metrics explained
Character encoding
Mapping between bytes and characters (UTF-8, Base64, hex, etc.).
Related concepts
Practical context
Use JWT Decoder when you need fast, private results without installing software. Results are computed locally unless the tool explicitly fetches public reference data.
Data & context
JWT structure
Three Base64URL segments: header (algorithm), payload (claims), signature (verification).
Common claims
| Claim | Meaning | Example |
|---|---|---|
| exp | Expiration time | Unix timestamp |
| iss | Issuer | auth.example.com |
| sub | Subject (user ID) | user_123 |
| aud | Audience | api.example.com |
Authoritative sources
- RFC Editor — Internet standards for encoding schemes.