What is OAuth 2.1?
OAuth 2.1 is the latest iteration of the OAuth authorization framework. It consolidates best practices and security improvements from OAuth 2.0, removing deprecated features and making PKCE mandatory.Key Improvements
Mandatory PKCE
All clients must use PKCE for authorization code flow
No Implicit Flow
Deprecated implicit and password grants removed
Redirect URI Matching
Exact matching required, no wildcards
Security First
Built-in protection against common attacks
OAuth 2.1 vs OAuth 2.0
| Feature | OAuth 2.0 | OAuth 2.1 |
|---|---|---|
| PKCE | Optional | Mandatory |
| Implicit Flow | Supported | Removed |
| Password Grant | Supported | Removed |
| Redirect URI | Substring match | Exact match |
| Refresh Token Rotation | Optional | Recommended |
Why OAuth 2.1?
1
Enhanced Security
PKCE prevents authorization code interception attacks
2
Simplified Spec
Removes deprecated and insecure flows
3
Modern Best Practices
Incorporates years of real-world experience
4
Future-Proof
Designed for current and future security threats