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JWT Decoder

Decode JWT tokens instantly to inspect header, payload, claims, and expiration data.

Tool

Use this free JWT Decoder to inspect JSON Web Tokens quickly in the browser. It helps you read JWT header and payload data, check common claims such as exp, iat, iss, aud, sub, and understand what a token contains during API development, authentication debugging, and integration testing. Paste a JWT token to decode it instantly without writing code or manually splitting Base64 URL segments.

About this tool

Use this free JWT Decoder to inspect JSON Web Tokens quickly in the browser. It helps you read JWT header and payload data, check common claims such as exp, iat, iss, aud, sub, and understand what a token contains during API development, authentication debugging, and integration testing. Paste a JWT token to decode it instantly without writing code or manually splitting Base64 URL segments.

Use jwt decoder when you need a fast browser-based result without extra setup. It works well for quick checks, one-off tasks, and routine formatting or calculation work.

When to use JWT Decoder

JWT Decoder vs related tools

JWT Decoder vs Base64 Decoder

JWT Decoder is built for full JWT tokens with dot-separated Base64 URL parts. Base64 Decoder is better for ordinary Base64 strings. If you are looking at an auth token rather than a plain encoded string, the JWT tool is the better fit.

JWT Decoder vs JWT Expiry Checker

JWT Decoder helps you inspect the full token content, including header and payload. JWT Expiry Checker is more focused on whether the token is expired or close to expiring. Use the decoder when you need full context, and the expiry checker when time-based validation is the main question.

Helpful next steps

If you mainly want to check whether a token is expired, open JWT Expiry Checker. If you want to inspect the token in a more parser-focused way, use JWT Parser. If you decode a claim that contains JSON or encoded text, you may also want JSON Formatter or Base64 Decoder.

Common mistakes when reading JWT tokens

Learn more

Why use this tool

How to use

  1. Paste the full JWT token into the input box
  2. Click Run Tool to decode the token
  3. Review the header and payload shown in readable JSON format
  4. Check important claims such as expiration time, issuer, subject, and audience
  5. If the token cannot be decoded, verify that you pasted all three token parts correctly

Examples

Example

Input

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.signature

Output

Header and Payload JSON

Useful when you want to inspect standard claims and basic token structure.

Example

Input

eyJhbGciOiJIUzI1NiJ9.eyJleHAiOjE3MzU2ODk2MDAsInN1YiI6InVzZXIxIn0.signature

Output

Decoded payload with exp claim

Helpful when debugging expired or soon-to-expire tokens.

Example

Input

eyJhbGciOiJSUzI1NiJ9.eyJpc3MiOiJodHRwczovL2F1dGguZXhhbXBsZS5jb20iLCJhdWQiOiJhcGktY2xpZW50Iiwic3ViIjoidXNlcjEyMyJ9.signature

Output

Decoded payload with iss, aud, and sub

Useful for checking whether the token was issued for the correct app or API.

Example

Input

eyJhbGciOiJIUzI1NiJ9.eyJyb2xlcyI6WyJhZG1pbiIsImVkaXRvciJdLCJwZXJtaXNzaW9ucyI6WyJyZWFkIiwid3JpdGUiXX0.signature

Output

Decoded payload with roles and permissions

Useful for debugging authorization problems and role-based access rules.

Example

Input

eyJhbGciOiJIUzI1NiJ9.eyJ0ZW5hbnQiOiJhY21lIiwidXNlcl90eXBlIjoicHJvIiwidGllciI6ImdvbGQifQ.signature

Output

Decoded payload with custom claims

Helpful when your app stores tenant, plan, or account information in custom fields.

Example

Input

eyJhbGciOiJSUzI1NiIsImtpZCI6IjEyMyJ9.eyJzdWIiOiJ1c2VyLTEiLCJlbWFpbCI6InVzZXJAZXhhbXBsZS5jb20iLCJleHAiOjE3MzU2ODk2MDAsImlhdCI6MTczNTYwMzIwMH0.signature

Output

Decoded header and payload with user and timing claims

Useful when checking whether the token content matches the user who just signed in.

Example

Input

eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjMifQ

Output

Invalid JWT

A JWT normally contains three dot-separated parts: header, payload, and signature.

Example

Input

invalid.token.value

Output

Invalid JWT

The decoder fails when token segments are not valid JWT data.

Common errors

Pasting only one or two token parts instead of the full JWT

Fix: Make sure the token includes all dot-separated sections and was copied completely.

Expecting the decoder to verify the signature automatically

Fix: Use the decoder to inspect content only. Signature validation is a separate step.

Confusing standard Base64 with JWT Base64 URL encoding

Fix: JWT uses Base64 URL encoding, so a JWT-specific tool is the right choice.

Assuming the token is valid just because it decodes

Fix: A token can decode successfully and still be expired, forged, or signed with an invalid key.

Reading exp or iat without checking timestamp meaning

Fix: Interpret claims like exp and iat as Unix timestamps and compare them carefully.

FAQ

What does a JWT decoder do?

A JWT decoder reads the token header and payload so you can inspect the claims inside a JSON Web Token.

Does decoding a JWT verify the signature?

No. Decoding only shows the token content. Signature verification is a separate security check.

What is the difference between JWT Decoder and Base64 Decoder?

JWT Decoder is designed for dot-separated JWT tokens that use Base64 URL segments, while Base64 Decoder is for standard Base64 strings.

Can I check JWT expiration with this tool?

Yes. If the token includes an exp claim, you can inspect it after decoding.

Why does my JWT fail to decode?

Common reasons include missing token parts, broken Base64 URL data, copy errors, or a value that is not actually a JWT.

Can I inspect roles, scopes, or permissions in a JWT?

Yes. If those values are present in the payload, this tool can help you read them.

What claims should I check first in a JWT?

The most useful claims to check first are usually exp, iat, iss, aud, sub, and any app-specific roles or scopes.

Is it safe to paste a JWT into a decoder?

That depends on how the page is implemented. If decoding happens client-side in the browser, the token is not sent elsewhere during the decode step.

Can I use this tool for access tokens and ID tokens?

Yes. It is useful for both, as long as the token is in JWT format.

Does a decoded JWT mean the user is authenticated correctly?

Not by itself. A decoded token may still be expired, invalidly signed, issued for the wrong audience, or otherwise unusable.

Use cases

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