Bearer Token is an access credential sent in the Authorization HTTP header that grants the holder ("bearer") access to a protected resource without additional identity proof.
Bearer Token
Bearer Token is an access credential sent in the Authorization HTTP header that grants the holder ("bearer") access to a protected resource without additional identity proof.
Why It Matters
Bearer tokens are the standard authentication mechanism for most modern APIs (RFC 6750). Their simplicity is both a strength and weakness — anyone holding the token has access, making them a high-value target for attackers.
How It Works
The client includes the token in the request header: `Authorization: Bearer <token>`. The server validates the token, extracts the associated identity and permissions, and processes the request. No additional proof of identity is required.
Best Practices
- Always transmit bearer tokens over HTTPS
- Set reasonable expiration times
- Store tokens securely (not in localStorage for web apps)
- Implement token revocation mechanisms
Common Mistakes
- Sending bearer tokens over unencrypted HTTP
- Storing tokens in browser localStorage (vulnerable to XSS)
- Creating bearer tokens that never expire
How ShieldKey Helps
ShieldKey's Shield Tokens function as bearer tokens but with added controls — IP restrictions, spend limits, and instant revocation that standard bearer tokens lack.
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What is a bearer token?
A bearer token is an access credential that grants API access to whoever holds it. It's sent in the Authorization header and requires no additional identity verification.