Utilitaires développeur

JWT Tool

Decode, sign, and verify JWT tokens locally.

Browser-onlyInstant outputLocal data

Les jetons sont signés localement dans votre navigateur. Ne partagez pas la clé.

Jeton JWT

Algorithme

HS256

Sujet

toolgrid

Expire le

11/12/2026 23:00:00

Header décodé

{
  "alg": "HS256",
  "typ": "JWT"
}

Payload décodé

{
  "sub": "toolgrid",
  "exp": 1797030000
}

Pourquoi utiliser cet outil

Inspect JWT claims, build HS256-signed tokens, and verify signatures in the browser.

JWT Tool combines decode, build, and verify in one place.

Sign tokens with HMAC-SHA256 and verify signatures locally without sending secrets to a server.

01Decode: paste any JWT to inspect header and payload claims.

02Build: provide a JSON payload and secret to produce a signed HS256 token.

03Verify: paste a token and secret to check whether the signature matches.

Confirm the input is the format you intended.

Scan the result before using it in a document, URL, config, or message.

Copy only the output you need.

Does the Decode tab verify signatures?

No. The Decode tab only inspects claims. Use the Verify tab to check signature validity.

Which algorithm does the Build tab use?

HS256 (HMAC-SHA256). The header is always set to alg: HS256, typ: JWT.

Are secrets sent to a server?

No. All signing and verification runs in your browser using the Web Crypto API.

Format, minify, and validate JSON in one place.

Convert plain text to Base64 and back.

Generate SHA-1, SHA-256, and SHA-512 hashes.