4 Best Free Online JWT Decoder Websites
Decode JSON Web Tokens online to read their header, payload and expiry time. These free JWT decoder websites also verify signatures and create test tokens.
Here is a list of best free online JWT decoder websites. A JSON Web Token (JWT) is a compact string used by most login systems and APIs to prove who a user is. It has three parts separated by dots: a header, a payload with claims such as the user ID and expiry time, and a signature. The header and payload are only Base64URL-encoded, not encrypted, so anyone can decode and read them.
A JWT decoder turns that string back into readable JSON. This is handy when debugging a login problem, checking why a token has expired or confirming which permissions a token carries.
A note on security:
A JWT is often a live credential. Anyone who has a valid access token can use it until it expires. Only paste test tokens or already-expired tokens into online tools, and prefer decoders that work entirely in your browser. For production tokens, decode them locally or wait until they have expired.
Top Pick:
jwt.io is the reference JWT debugger. It decodes tokens, verifies signatures and creates new tokens, and it has been the go-to tool for developers for years.
Comparison Table:
| Website | Decode header and payload | Verify signature | Create/sign tokens |
|---|---|---|---|
| jwt.io | ✓ | ✓ | ✓ |
| jwt.ms | ✓ | x | x |
| token.dev | ✓ | ✓ | ✓ |
| IT Tools | ✓ | x | x |
jwt.io
jwt.io is the JWT debugger presented by Auth0 (now part of Okta). Paste a token, and it shows the decoded header and payload side by side, with timestamps such as exp and iat explained. Enter a secret or public key to verify the signature, or switch to the encoder to generate a token for testing.
The site also lists JWT libraries for most programming languages.
| Pros | Cons |
|---|---|
| Decode, verify and create tokens | Don’t paste live production tokens |
| Explains standard claims | |
| Long-standing reference tool |
jwt.ms
jwt.ms is a simple JWT decoder run by Microsoft. It shows the decoded token and has a Claims tab that explains each claim, which is especially useful for tokens issued by Microsoft Entra ID (Azure AD). It is a decoder only: it does not verify signatures or create tokens.
| Pros | Cons |
|---|---|
| Clean, minimal interface | Decode only |
| Claims tab explains each field | Mainly aimed at Microsoft tokens |
token.dev
token.dev is a JWT playground. Besides decoding, it lets you edit the header and payload and re-sign the token with a chosen algorithm and key, so you can see how changes affect the encoded string. That makes it a good learning tool and useful for creating test tokens.
| Pros | Cons |
|---|---|
| Edit and re-sign tokens | More options than a quick decode needs |
| Supports several signing algorithms | |
| Good for learning how JWTs work |
IT Tools
IT Tools is an open-source collection of developer utilities, and its JWT parser decodes a token into a readable table of header and payload values. Because the whole project is open source, you can also self-host it and decode tokens on your own server, which avoids pasting tokens into a third-party site at all. The collection includes dozens of other tools such as Base64, hash and UUID generators.
| Pros | Cons |
|---|---|
| Open source and self-hostable | Decode only, no signature check |
| Dozens of other developer tools |
Final Thoughts:
Use jwt.io when you need the full set of decode, verify and create features, jwt.ms for a quick look at Microsoft tokens, token.dev to experiment with signing, and a self-hosted IT Tools instance when privacy matters most. Whatever you choose, treat live tokens like passwords.
