How to Decode a JWT Token Online for Free — Browser Tool
Inspect JWT header, payload, and signature without sending your token to any server — decoded instantly in your browser.
Decode JWT Token Online — Free & Private
Inspect JWT header, payload, and signature without sending your token to any server — decode and read the claims, expiry time, and issuer details of any JSON Web Token entirely in your browser.
JWT tokens carry authentication claims, user roles, and expiry times. This decoder splits and decodes the Base64url-encoded header and payload locally so your auth tokens never touch an external server.
How to Decode a JWT Token Online
Step 1: Paste Your JWT
Paste the full JWT string (header.payload.signature) into the input field. The three base64url-encoded parts are separated by dots.
Step 2: Click Decode
Press Decode. The tool splits the token and base64url-decodes each part to reveal the JSON header and payload.
Step 3: View Header and Payload
Read the decoded header (algorithm, type) and payload (sub, iat, exp, roles, and any custom claims) in formatted JSON panels.
Step 4: Verify the Signature
Optionally provide your secret or public key to verify the token signature and confirm it hasn't been tampered with.
Why Use This JWT Decoder?
Completely Private
Your JWT token — which may contain user roles and session data — never leaves your browser.
Instant Decoding
Header and payload decode immediately using client-side Base64url decoding.
Signature Verification
Optionally verify the token signature using your HMAC secret or RSA public key.
Decode JWT Token — No Upload Required
Runs entirely in your browser — no upload, no account, no waiting.
Related guides
Developer Tools
Decode Base64 Online Free
Decode Base64-encoded strings back to plain text entirely in your browser.
Developer Tools
How to Format JSON Online
Prettify and format JSON with proper indentation for readability.
Privacy
Developer Tools Privacy Guide
Why developer tools like JWT decoders should never send your tokens to a server.