API pricing calculator

API Cost Calculator

Estimate monthly request-processing and bandwidth costs for a REST API with your own provider rates and free-tier allowances.

Estimated monthly cost

$5.29USD / month

Total API bandwidth57.2 GBrequests + responses

Outbound data47.7 GBresponses only

Request cost: $1.00
Bandwidth cost: $4.29
Monthly estimate: $5.29

Annual estimate$63.50Cost per request$0.000005Requests per month1M

How this estimate works

1,000,000 — Billable requests ÷ 1,000,000 × request price

47.7 GB — Billable response data × outbound price per GB

This is an estimate, not a provider quote. Add database, compute, logging, cache, gateway, tax, and regional charges separately when they apply.

Three inputs, one clear estimate

How to calculate API costs

Estimate monthly requests

Use logs or expected active users to enter the number of API calls your service handles each month.

Measure payload sizes

Enter average request and response payload sizes in KB. The calculator separates inbound and outbound transfer.

Add your provider rates

Copy request and egress prices from your provider, then include any monthly free-tier allowances.

Transparent assumptions

What the API cost estimate includes

Request processing

The request charge is based on billable calls after the free request allowance.

Bandwidth and egress

Total bandwidth includes request and response payloads. Cost uses outbound response data because egress is commonly billed.

Provider-neutral rates

All price fields are editable, so the calculator works for API gateways, serverless platforms, and self-hosted REST APIs.

Common questions

API cost calculator FAQ

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How is API bandwidth calculated?

Total bandwidth equals monthly requests multiplied by the combined average request and response size. This calculator uses 1 GB = 1,048,576 KB.

Why is only response data used for bandwidth cost?

Cloud providers commonly charge for outbound internet transfer while inbound data is free. If your provider charges both directions, add its combined effective rate or include the extra cost separately.

Does this include serverless compute or database costs?

No. The result covers the request rate and outbound data rate you enter. Add compute duration, database operations, storage, observability, and other provider-specific charges separately.

Can I use this for REST API pricing?

Yes. It works for REST, JSON, GraphQL, webhook, and other request-response APIs when you know average request volume and payload sizes.

Are the default prices tied to a provider?

No. The defaults are an editable example only. Replace them with the current prices and free tiers from your provider.