sub
Subject claim — unique identifier for the user or entity the token represents.
Quick Answer
See our full JWT Glossary for related terms, or use the JWT Decoder to inspect tokens in practice.
What is sub?
Subject claim — unique identifier for the user or entity the token represents.
See It in Practice
Paste any JWT into our JWT Decoder to see related claims in action. Use the JWT Debugger for detailed analysis.
Related
Browse the full JWT Glossary or explore JWT Basics.
sub in JWT Authentication
Understanding sub helps you read RFC 7519, debug tokens, and design secure authentication. JWTs combine header, payload claims, and a cryptographic signature.
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