What does AWS API Gateway charge per request?

AWS API Gateway charges $3.50 per million REST API calls for the first 333 million, decreasing to $2.80 and then $2.38 at higher tiers. HTTP APIs are cheaper at $1.00 per million. WebSocket APIs charge $1.00 per million messages plus connection minutes.

Are there hidden costs beyond per-call pricing?

Yes. Consider data transfer costs for response payloads, caching charges if you enable API Gateway caching, CloudWatch logging costs, and any backend compute triggered by each API call (Lambda, EC2, etc.).

How do I reduce API call volume?

Implement client-side caching with appropriate TTLs, use CDN caching for public endpoints, batch requests where the API supports it, switch from polling to webhooks or WebSockets, and deduplicate redundant calls in your application code. Consulting relevant industry guidelines or professional resources can provide additional context tailored to your specific circumstances and constraints.

What's the difference between REST and HTTP APIs?

AWS HTTP APIs are simpler and up to 71% cheaper than REST APIs. REST APIs offer more features like caching, request validation, and WAF integration. For basic proxy and Lambda integrations, HTTP APIs are usually the better choice.

When should I self-host instead of using API Gateway?

Self-hosting makes sense when call volumes exceed tens of millions per month, you need sub-millisecond latency, or you require custom routing logic. An NGINX or Envoy proxy on EC2/ECS can be much cheaper at scale.

How do tiered pricing models work?

Tiered pricing charges different rates at different volume bands. For example, the first million calls might cost $3.50/million, the next 10 million at $2.80/million, and everything above at $2.38/million. Your total cost blends these tiers.

API Call Cost Calculator

Calculate the cost of API calls based on total requests, pricing tiers, and rate limits. Budget your API gateway and third-party API expenses.

Pricing Model

Monthly API Calls

Free Tier Calls

Monthly Base Fee

Avg Payload Size

Data Transfer Rate

$/GB

Tier Definition (e.g. 1M@3.50,100M@2.80,1B@2.38)

Total Monthly Cost

$4,420.43

API $25.90 + Data $4,394.53 + Base $0.00

Annual Cost

$53,045.17

12-month projection at current usage

Billable Calls

9,000,000.00

10,000,000.00 total minus 1,000,000.00 free

API Variable Cost

$25.90

Effective rate: $2.88/million

Data Transfer Cost

$4,394.53

48828.13 GB at $0.09/GB

Free Tier Savings

$3.50/mo

1,000,000.00 calls covered free

Cost per 1,000 Calls

$0.442

All-in blended cost

Cost per Call

$0.000442

Unit economics per API request

Cost Distribution

API Calls

$25.90 (0.01%)

Data Transfer

$4,394.53 (0.99%)

Base Fee

$0.00 (0.00%)

Tiered Pricing Breakdown

Tier Range	Calls in Tier	Rate ($/M)	Tier Cost
1.00 - 1,000,000.00	1,000,000.00	$3.50	$3.50
1,000,001.00 - 100,000,000.00	8,000,000.00	$2.80	$22.40
Total	9,000,000.00	$2.88 avg	$25.90

Volume Scaling Table

Monthly Calls	Billable	API Cost	Data Cost	Total	Per 1K Calls
100,000.00	0.00	$0.00	$43.95	$43.95	$0.4395
500,000.00	0.00	$0.00	$219.73	$219.73	$0.4395
1,000,000.00	0.00	$0.00	$439.45	$439.45	$0.4395
5,000,000.00	4,000,000.00	$11.90	$2,197.27	$2,209.17	$0.4418
10,000,000.00 *	9,000,000.00	$25.90	$4,394.53	$4,420.43	$0.442
50,000,000.00	49,000,000.00	$137.90	$21,972.66	$22,110.56	$0.4422
100,000,000.00	99,000,000.00	$277.90	$43,945.31	$44,223.21	$0.4422

Planning notes, formulas, and examples

About the API Call Cost Calculator

APIs are the connective tissue of modern applications, but every call comes with a price tag. Whether you're using AWS API Gateway, a third-party service like Twilio or Stripe, or building your own monetized API, understanding per-call costs is critical for budgeting and architecture decisions.

API pricing models vary widely. Cloud API gateways typically charge per million requests with tiered pricing that decreases at higher volumes. Third-party APIs may charge flat per-call rates, monthly subscriptions with quotas, or usage-based tiers. Some APIs even charge differently for reads vs writes or by endpoint.

This calculator lets you model your monthly API costs based on call volume, per-call rate, and optional tiered pricing. Use it to forecast expenses, compare providers, and determine when self-hosting an API becomes more economical.

When This Page Helps

API costs can quietly consume a large portion of your cloud budget, especially when microservices architectures multiply internal call volumes. This calculator helps you forecast monthly API expenses accurately, compare pricing across providers, and identify optimization opportunities like caching, request batching, or moving to a different pricing tier.

How to Use the Inputs

Enter the total number of API calls you expect per month.
Set the cost per call (or per million calls, then divide accordingly).
Optionally enter a free tier or included quota to subtract.
Enter any fixed monthly subscription or base fee.
Review the total monthly cost including both fixed and variable components.
Adjust volumes to model growth scenarios.

Formula used

Billable Calls = max(0, total_calls − free_tier_calls)
Variable Cost = billable_calls × cost_per_call
Total Monthly Cost = base_fee + variable_cost

Example Calculation

Result: $14.00/month

Five million API calls with 1 million free tier calls leaves 4 million billable calls. At $3.50 per million ($0.0000035 per call), the monthly cost is $14.00.

Tips & Best Practices

Implement caching to reduce redundant API calls and lower costs.
Batch multiple operations into single API calls where supported.
Use API Gateway usage plans with throttling to prevent runaway costs.
Monitor actual API usage weekly and set billing alerts at threshold levels.
Consider WebSocket connections for real-time data instead of polling APIs.
Evaluate whether a higher-tier plan with a lower per-call rate saves money.

API Gateway Pricing Comparison

AWS API Gateway REST APIs charge $3.50/million, while HTTP APIs charge $1.00/million. Google Cloud API Gateway is free for up to 2 million calls and $3.00/million after. Azure API Management pricing depends on the tier, starting at $0.035/10,000 calls in Consumption tier. Compare providers based on your actual call patterns.

Controlling API Costs at Scale

At high volumes, API costs add up quickly. Key strategies include implementing response caching at the gateway level, using request batching to combine multiple operations, rate limiting to prevent abuse, and moving high-volume internal communication to direct service calls instead of routing through the gateway.

API Monetization Considerations

If you're building an API product, infrastructure cost per call directly impacts margins. Understanding your per-call cost helps you set sustainable pricing, define free tier limits, and project profitability at different usage volumes.

Sources & Methodology

Last updated: February 8, 2026

Frequently Asked Questions

AWS API Gateway charges $3.50 per million REST API calls for the first 333 million, decreasing to $2.80 and then $2.38 at higher tiers. HTTP APIs are cheaper at $1.00 per million. WebSocket APIs charge $1.00 per million messages plus connection minutes.