ToolHub

JWT デコーダー & インスペクタ

ヘッダー / ペイロードをローカルでデコード


            

            

              
              

            

          

          
          

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JWT デコーダー / インスペクタ

        
Paste a JWT (or 'Bearer <token>') and instantly see its decoded header and payload, with iat / exp / nbf timestamps annotated as ISO dates. Designed for quick debugging of API responses, OIDC flows and access tokens. Local-only.

        
  • Decodes header, payload and signature
  • Annotates iat / exp / nbf as ISO timestamps
  • Detects expired tokens
  • Tolerates 'Bearer ' prefix
  • Runs locally — token never sent
  • HS / RS / ES / PS compatible (decode only)

      


      

        
FAQ

        
    

      Does this verify the signature?
      
No. This tool only decodes the segments. Signature verification needs the secret or public key, which we deliberately do not collect.

    

    

      Is it safe to paste a real production token?
      
Decoding happens entirely in your browser. Still, treat any token pasted into a browser as potentially observed by extensions; rotate if in doubt.