nbf
Not Before claim — Unix timestamp before which the token must not be accepted. Prevents premature use.
Quick Answer
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What is nbf?
Not Before claim — Unix timestamp before which the token must not be accepted. Prevents premature use.
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Related
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nbf in JWT Authentication
Understanding nbf helps you read RFC 7519, debug tokens, and design secure authentication. JWTs combine header, payload claims, and a cryptographic signature.
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