JWT (JSON Web Token) is a compact, URL-safe token format used for authentication and information exchange. It consists of three parts: header, payload, and signature.

Can this tool verify JWT signatures?

No. This tool decodes JWT payloads for inspection. Signature verification requires the secret key, which should never be shared.

ToolboxPro

JWT Decoder

Decode JWT tokens and inspect header, payload, and signature

Processing on your device — files never leave your browser

How to Use This Tool

A JWT (JSON Web Token) decoder that inspects the contents of authentication tokens. Paste a JWT string (three Base64URL-encoded segments separated by dots) and the tool instantly decodes the header and payload into readable JSON. The decoded view shows all standard claims: subject, issuer, audience, expiration, issued-at, and not-before — with human-readable timestamps converted from Unix epoch. The tool highlights expired tokens and shows exactly how much time remains until expiration. Developers use this tool when debugging authentication failures: checking why a token is rejected, verifying claim values match expected configuration, or comparing tokens issued by different auth providers. The tool also detects the signature algorithm (HS256, RS256, etc.) and warns about insecure algorithms like 'none'.

How It Compares

See how JWT Decoder stacks up against alternatives:

Feature	ToolboxPro	jwt.io
100% client-side — token never leaves browser	✅	⚠️
Clear header/payload/signature display	✅	⚠️
No security risk for sensitive tokens	✅	⚠️
Supports all JWT algorithms	✅	⚠️
Fully Free / No Signup	✅	⚠️
100% Privacy (No Upload)	✅	❌

jwt.io

+ Industry standard

+ Debug features

- Server-side (sends token)

- Complex interface

- Security concern with sensitive tokens

💡 What can I use this for?

Debug Auth Tokens

Decode a JWT from the browser local storage to inspect the header algorithm and payload claims like exp and sub.

Verify Token Expiry

Check the exp claim of a JWT to determine if an expired token is causing 401 errors in API requests.

SSO Integration Debug

Decode the identity token returned by an OIDC provider to verify the user claims and issuer are correct.

Frequently Asked Questions

JSON Formatter & Validator Base64 Encoder/Decoder Regex Tester Color Converter URL Encoder/Decoder UUID Generator Hash Generator Timestamp Converter

Developer Tools5 min read

JWT Decoder: How to Decode and Inspect JSON Web Tokens

Learn to decode JSON Web Tokens, inspect header and payload claims, verify signatures, and debug authentication issues with our free JWT decoder.

JWT Decoder

Decode JWT tokens and inspect header, payload, and signature

Processing on your device — files never leave your browser

How to Use This Tool

How It Compares

See how JWT Decoder stacks up against alternatives:

Feature	ToolboxPro	jwt.io
100% client-side — token never leaves browser	✅	⚠️
Clear header/payload/signature display	✅	⚠️
No security risk for sensitive tokens	✅	⚠️
Supports all JWT algorithms	✅	⚠️
Fully Free / No Signup	✅	⚠️
100% Privacy (No Upload)	✅	❌

jwt.io

+ Industry standard

+ Debug features

- Server-side (sends token)

- Complex interface

- Security concern with sensitive tokens

💡 What can I use this for?

Debug Auth Tokens

Decode a JWT from the browser local storage to inspect the header algorithm and payload claims like exp and sub.

Verify Token Expiry

Check the exp claim of a JWT to determine if an expired token is causing 401 errors in API requests.

SSO Integration Debug

Decode the identity token returned by an OIDC provider to verify the user claims and issuer are correct.

Frequently Asked Questions

JSON Formatter & Validator Base64 Encoder/Decoder Regex Tester Color Converter URL Encoder/Decoder UUID Generator Hash Generator Timestamp Converter

Developer Tools5 min read

JWT Decoder: How to Decode and Inspect JSON Web Tokens

Learn to decode JSON Web Tokens, inspect header and payload claims, verify signatures, and debug authentication issues with our free JWT decoder.

JWT Decoder

📖How to Use This Tool

⚖️How It Compares

jwt.io

💡 What can I use this for?

Debug Auth Tokens

Verify Token Expiry

SSO Integration Debug

Frequently Asked Questions

Related Tools

Related Articles

JWT Decoder: How to Decode and Inspect JSON Web Tokens

JWT Decoder

📖How to Use This Tool

⚖️How It Compares

jwt.io

💡 What can I use this for?

Debug Auth Tokens

Verify Token Expiry

SSO Integration Debug

Frequently Asked Questions

Related Tools

Related Articles

JWT Decoder: How to Decode and Inspect JSON Web Tokens

How to Use This Tool

How It Compares

How to Use This Tool

How It Compares