JWT Decoder & Verifier

Decode JWT tokens, inspect claims, and verify HS256, HS384, or HS512 signatures online without exposing secrets.

Secrets are used locally via the Web Crypto API.

Token breakdown

JWTs consist of three Base64URL segments: header, payload, and signature. Each segment is decoded locally and never leaves your browser.

Need to debug tokens from production? Paste them directly—no data is sent to Batch Toolkit.

Tips
  • Always check the expiry before trusting a token in tooling workflows.
  • Verify signatures using known secrets when debugging authentication flows.
  • JWTs often include sensitive claims—avoid sharing decoded payloads publicly.

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