AWS · Free tool
AWS API Gateway cost calculator
REST API and HTTP API look similar in the console. The bills do not. Plug in your traffic, see all three flavors side by side, and see the dollar number on a HTTP API migration.
Side-by-side monthly cost
REST API
$0
$3.50 / 1M (tiered)
HTTP API
$0
$1.00 / 1M (tiered, payload-aware)
WebSocket API
$0
$1.00 / 1M msgs + $0.25 / 1M conn-min
REST -> HTTP API migration value
Where API Gateway bills sneak up on teams
- REST APIs left in production from the early-2020 default that nobody migrated. Free 71 percent saving for most.
- WebSocket clients that never disconnect. Idle connections rack up connection-minutes 24/7.
- HTTP API charging extra 512 KB chunks because the request payload tipped over a kilobyte boundary.
- CloudWatch Logs from API Gateway access logs at full verbosity, billed separately, often more than the gateway itself.
- Custom domain names and ACM cert renewals that quietly add Route 53 query charges per resolution.
REST or HTTP, pick once and stop paying for both
AWS launched HTTP API in 2020 as the modern, slimmer successor to REST API. The discount has been 71 percent on requests since day one, and most teams who started before 2020 are still on REST because the migration was never urgent enough.
For a 100M-request-per-month API, the monthly difference is around $250. For 1B requests, it is $2,500. Multiplied by the number of stages and accounts most teams run, this is the cleanest savings line in the AWS catalog. The full migration playbook is in REST vs HTTP API: the 71 percent discount.
Run this on your real account
Free 14-day audit, read-only IAM role, one-page CFO summary.
We pull your API Gateway inventory across stages and accounts, flag REST APIs that should be HTTP APIs, surface idle WebSocket connection-minute drift, and quantify the migration. The audit is free, the report is yours.
Frequently asked
How is API Gateway priced exactly?
Three flavors with different rates. REST API charges $3.50 per million requests for the first 333 million per month, dropping in tiers. HTTP API charges $1.00 per million requests, a 71 percent discount on REST. WebSocket API charges $1.00 per million messages plus $0.25 per million connection-minutes. Data transfer charges apply on top.
Why is HTTP API so much cheaper than REST API?
HTTP API is a slimmer service. It dropped some REST features that most production teams never use: usage plans and API keys, request validation, request transformation, and AWS WAF native integration (you can still attach WAF in front of an HTTP API). Most teams who reach for those features can replicate them at the application layer or in front of HTTP API. The 71 percent saving is real for almost any new API.
When should I stay on REST API?
Two reasons. One, you depend on private REST APIs in a VPC behind PrivateLink (HTTP API supports private endpoints differently). Two, you have a Cognito User Pool with REST-API-specific features like API key throttling and usage plans the team uses for monetization. For everything else, HTTP API is the modern default.
What about WebSocket API pricing surprises?
WebSocket bills two dimensions: messages and connection-minutes. Long-lived connections at $0.25 per million minutes look harmless until you have 50,000 concurrent connections for 30 days, which is 50,000 × 60 × 24 × 30 = 2.16 billion connection-minutes, or $540 a month before any messages flow. Disconnect idle clients aggressively and use one connection for many message types.
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