What is the difference between REST API and HTTP API pricing?

HTTP APIs are up to 71% cheaper than REST APIs for the same request volume. REST APIs cost $3.50 per million requests (first 333 million), while HTTP APIs cost $1.00 per million. However, REST APIs include features like request validation, WAF integration, and API caching that HTTP APIs lack.

How does API Gateway caching work?

REST APIs support a fully managed cache (0.5 GB to 237 GB) that stores backend responses for a configurable TTL. Cached responses are served without invoking the backend, reducing latency and cost. Cache pricing is per-hour based on cache size, separate from request charges. HTTP APIs do not support built-in caching.

Is there a free tier for API Gateway?

Yes. AWS offers 1 million REST API calls and 1 million HTTP API calls per month free for the first 12 months of a new account. WebSocket APIs include 1 million messages and 750,000 connection minutes per month in the free tier.

API Gateway Cost Estimator

ServerlessAWS

Estimate API Gateway costs for REST, HTTP, and WebSocket APIs with caching, data transfer, and side-by-side comparison.

Last verified: April 2026

Input

Example Presets

API Type

Requests per month (millions)

10,000,000 requests

Enable API caching

Avg response size (KB)

Show side-by-side comparison (REST vs HTTP vs WebSocket)

About This Tool

The API Gateway Cost Estimator calculates monthly costs for AWS API Gateway across REST, HTTP, and WebSocket API types. It accounts for request volume, data transfer, caching (REST API only), and the differences in per-request pricing between API types. The tool provides side-by-side comparisons to help you choose the most cost-effective API type for your use case.

Real-World Scenario

You are running a REST API with 5 million requests per month and paying $17.50 in request charges plus $14.40 for a 0.5 GB cache. Your API only uses Lambda proxy integration and JWT auth. You use the estimator to model switching to HTTP API and see request costs drop to $5.00. You lose the built-in cache but add CloudFront in front for $1.00, netting a $25.90/month savings.

When to Use This Tool

•Comparing REST API vs. HTTP API pricing for a new serverless API to determine cost savings from HTTP API migration.
•Estimating caching costs for a REST API to understand the ROI of reducing backend invocations.
•Calculating WebSocket API costs for a real-time messaging application based on connection minutes and message volume.
•Modeling data transfer costs for APIs that return large payloads to understand total API cost beyond request charges.

Pro Tips

TIP

HTTP APIs are up to 71% cheaper than REST APIs and support most common use cases including JWT authorization, CORS, and Lambda/HTTP integrations. Unless you specifically need REST API features like request validation, WAF integration, API keys, or caching, always choose HTTP API.

TIP

REST API caching can dramatically reduce Lambda invocation costs, but the cache runs 24/7 and charges per hour regardless of hit rate. A 0.5 GB cache costs about $15/month. Calculate your Lambda savings from cache hits before enabling it, or you may pay more for caching than you save.

TIP

API Gateway data transfer charges are separate from request charges and often overlooked. If your API returns 1 MB responses at 1 million requests per month, that is 1 TB of data transfer at $0.09/GB, adding $90 to your bill on top of request fees.

How It Works Under the Hood

The estimator multiplies request volume by the per-million rate for each API type (REST at $3.50, HTTP at $1.00, WebSocket at $1.00 per million messages plus $0.25 per million connection minutes). Caching cost is calculated as cache size times hourly rate times 730 hours per month. Data transfer is computed from average response size times request count, with the first 1 GB free and tiered pricing beyond that.

Frequently Asked Questions

What is the difference between REST API and HTTP API pricing?: HTTP APIs are up to 71% cheaper than REST APIs for the same request volume. REST APIs cost $3.50 per million requests (first 333 million), while HTTP APIs cost $1.00 per million. However, REST APIs include features like request validation, WAF integration, and API caching that HTTP APIs lack.
How does API Gateway caching work?: REST APIs support a fully managed cache (0.5 GB to 237 GB) that stores backend responses for a configurable TTL. Cached responses are served without invoking the backend, reducing latency and cost. Cache pricing is per-hour based on cache size, separate from request charges. HTTP APIs do not support built-in caching.
Is there a free tier for API Gateway?: Yes. AWS offers 1 million REST API calls and 1 million HTTP API calls per month free for the first 12 months of a new account. WebSocket APIs include 1 million messages and 750,000 connection minutes per month in the free tier.

Related Learning Guides

API Gateway Complete Guide24 min read
Cost Optimization Strategies26 min read

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