API Gateway REST API versus ALB WebSocket

13 Mar 2026

Learn how API Gateway REST API differs from ALB WebSocket.

	API Gateway REST API	ALB WebSocket
Type	REST API	Websocket
HTTPS/TLS	✅	✅
Backends	✅ Lambda ✅ Public endpoint ✅ Private endpoint ✅ AWS Service APIs	❌ Lambda ❌ Public endpoint ✅ Private endpoint ❌ AWS Service APIs
Costs	💰💰	💰💰
Maturity	⭐️⭐️⭐️⭐️⭐️	⭐️⭐️⭐️⭐️
Authentication	✅ IAM ✅ API Key ✅ OpenID Connect ✅ SAML ✅ Social ✅ Custom	❌ IAM ❌ API Key ✅ OpenID Connect ✅ SAML ✅ Social ❌ Custom
Tenant-based Throttling	✅	❌
Request Validation	✅	❌
Req./Res. Transformation	✅	❌
Endpoints	✅ Public ✅ Private	✅ Public ✅ Private
WAF	✅	✅

Further reading