API Gateway Cost Calculator

Plan gateway spending with flexible usage assumptions. Model request, transfer, cache, and monitoring charges precisely. See savings scenarios, exports, charts, and cost drivers instantly.

Calculator Inputs

This calculator is provider-agnostic. Enter your own pricing and traffic values to model monthly cost, annual run rate, and growth-adjusted spend.

Traffic Inputs

Request Pricing

Transfer Pricing

Cache Settings

Logging Costs

Fixed Monthly Add-Ons

Scenario Controls

Reset

Example Data Table

This sample uses the default values already loaded in the form.

Monthly Requests Processed Data Request Cost Transfer Cost Cache Cost Log Costs Fixed Add-Ons Total Monthly Cost
12,000,000 286.10 GB $38.50 $25.66 $29.20 $7.92 $99.20 $216.51

Formula Used

Processed Data (GB) = Monthly Requests × (Average Request KB + Average Response KB) ÷ 1024 ÷ 1024

Billable Requests = Max(0, Monthly Requests − Free Requests)

Request Cost = (Billable Requests ÷ 1,000,000) × Request Rate per 1M

Billable Data (GB) = Max(0, Processed Data GB − Free Data GB)

Data Transfer Cost = Billable Data GB × Data Rate per GB

Cache Cost = Cache Hours × Cache Hourly Rate

Log Volume (GB) = Monthly Requests × Log KB per Request ÷ 1024 ÷ 1024

Log Ingestion Cost = Log Volume GB × Log Ingest Rate per GB

Log Retention Cost = Retained Log GB × Retention Rate per GB

Authorizer Cost = (Authorizer Requests ÷ 1,000,000) × Authorizer Rate per 1M

Subtotal = Request Cost + Transfer Cost + Cache Cost + Log Costs + Authorizer Cost + Fixed Add-Ons

Contingency Reserve = Subtotal × Contingency Percentage

Total Monthly Cost = Subtotal + Contingency Reserve

Annual Run Rate = Total Monthly Cost × 12

Projected Month N = Total Monthly Cost × (1 + Growth Rate)N−1

How to Use This Calculator

  1. Enter your expected monthly API request count.
  2. Add average request and response sizes to estimate transfer volume.
  3. Fill in the free request and free transfer allowances from your pricing plan.
  4. Enter request, transfer, authorizer, cache, logging, and retention rates.
  5. Add fixed monthly costs such as monitoring, WAF, custom domain, and support.
  6. Set a contingency percentage for overages, retries, and unknowns.
  7. Set a monthly growth percentage to project future spending trends.
  8. Click Calculate Cost to view the summary, breakdown table, exports, and Plotly chart.

FAQs

1. What costs does this calculator include?

It combines billable requests, data transfer, cache runtime, log ingestion, log retention, authorizer usage, monitoring, support, custom domain, WAF, and contingency reserve.

2. Can I use this for any cloud provider?

Yes. The model is provider-agnostic. Enter the exact pricing values from your own vendor plan, region, and traffic profile to get a tailored estimate.

3. Why do request and response sizes matter?

They estimate processed traffic volume. Larger payloads increase transfer-related cost and can also affect logging, observability, and downstream networking expenses.

4. What is the contingency percentage for?

It adds a planning buffer for retries, traffic spikes, bad actors, regional changes, pricing drift, or small overlooked charges that appear after deployment.

5. Does enabling cache always lower total cost?

Not always. Cache adds runtime cost. It pays off when it reduces backend load, origin transfer, or expensive downstream calls more than the cache itself costs.

6. How should I estimate log volume per request?

Start with a sample from your current logs. Measure average bytes written for request, response, trace, and error entries, then convert to kilobytes.

7. Why is year-one projected total different from annual run rate?

Annual run rate assumes the same monthly spend for twelve months. Year-one projection increases or decreases each month using your growth assumption.

8. Should I include support and security charges?

Yes. Real gateway budgets usually include observability, security controls, and internal support overhead. Leaving them out can understate true operating cost.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.