JWT Decoder Online Free | MyToolbox

Decode JSON Web Tokens and inspect header, payload, and signature. Free JWT decoder for developers. Runs in your browser.

How to Use JWT Decoder

1

Paste your JWT

Paste the full JWT string (the three dot-separated Base64 segments) into the input field.
2

View decoded sections

The tool instantly decodes and displays the header (algorithm and type), payload (claims and data), and signature in a readable format.
3

Inspect claims

Review the payload claims: issuer, subject, expiration time, issued-at time, custom claims, and more. Timestamps are shown in human-readable format.

Why Use Our JWT Decoder

Instant Decoding

Paste a JWT and see the decoded header and payload immediately. No clicking required — decoding happens as you paste.

Human-Readable Timestamps

Unix timestamps in exp, iat, and nbf claims are automatically converted to readable dates and times so you can quickly check expiration.

Header, Payload, Signature

All three JWT sections are displayed separately with proper formatting: the header shows the algorithm, the payload shows all claims, and the signature is displayed as-is.

Pretty-Printed JSON

The decoded header and payload are formatted as indented, syntax-highlighted JSON for easy reading.

Client-Side Only

Your JWT never leaves your browser. This is essential since JWTs often contain sensitive authentication data.

Frequently Asked Questions

Is the JWT decoder free?

Yes, completely free. Decode as many tokens as you need with no signup and no limits.

Is it safe to paste my JWT here?

Yes. The decoding happens entirely in your browser. Your token is never sent to any server. This is important because JWTs can contain sensitive user data and authentication information.

What information can I see in a decoded JWT?

The header shows the signing algorithm (e.g., HS256, RS256) and token type. The payload contains claims like issuer (iss), subject (sub), expiration (exp), and any custom data the application included.

Can I use this to debug authentication issues?

Yes. Common debugging tasks include checking if a token has expired (exp claim), verifying the issuer (iss), confirming the audience (aud), and inspecting custom claims.

How does this compare to jwt.io?

jwt.io is the most well-known JWT tool. MyToolbox offers the same decoding functionality with a cleaner interface and without sending your token data through a third-party service.

Does this tool verify the JWT signature?

The tool decodes and displays the JWT contents. Signature verification requires the secret key or public key, which is a separate operation typically done server-side.

Does this work on mobile?

Yes. Paste JWTs from your clipboard in any mobile browser. The decoded output is formatted for easy reading on any screen size.

Can I decode expired tokens?

Yes. The decoder shows all token content regardless of expiration status. Expired tokens are decoded the same way — you can inspect when and why they expired.