API Gateway Pricing Calculator - HTTP, REST, WebSocket APIs

HTTP APIs are up to 71% cheaper and optimized for serverless workloads with Lambda/HTTP backends. They support JWT authorization and CORS. REST APIs offer full API management including caching, request validation, API keys, usage plans, and AWS WAF integration. Choose HTTP APIs for simple proxies, REST APIs for enterprise features.

WebSocket APIs charge for messages ($1.00 per million) and connection minutes ($0.25 per million). Messages are metered in 32 KB increments, so a 33 KB message counts as two. Connection minutes are the total time all clients are connected. For a chat app with 1000 users connected 12 hours daily, expect ~21.6M connection minutes/month.

HTTP APIs are metered in 512 KB request increments. A 600 KB request counts as 2 billable requests. REST APIs with Response Streaming are metered in 10 MB response payload increments. A 65 MB response counts as 7 billable requests. Standard REST APIs charge per request regardless of size.

Caching is available for REST APIs and charges hourly by size (from $0.02/hr for 0.5 GB to $3.80/hr for 237 GB). Use caching when your backend responses are cacheable and you want to reduce latency and backend load. For a 1.6 GB cache running 24/7, expect ~$27/month. Caching is not available for HTTP APIs or WebSocket APIs.

Private REST APIs are only accessible within your VPC via AWS PrivateLink. In addition to standard REST API call charges, you pay for the VPC endpoint: $0.01/AZ/hour (about $7.30/month per AZ) plus $0.01/GB data processed. Factor in these costs when designing internal APIs.

The AWS Free Tier includes 1 million REST API calls, 1 million HTTP API calls, 1 million WebSocket messages, and 750,000 connection minutes per month for the first 12 months. This calculator automatically deducts free tier usage when enabled.