Request fees vs bandwidth
Small responses stay request-bound, big JSON or media payloads tip the bill toward egress.
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API & Backend Cost
REST API Cost Calculator
Estimate the monthly cost of a REST API. Enter request volume, per-request pricing and average response size, and see request fees, bandwidth and how the bill grows.
Estimated monthly cost
$0
Request cost—
Bandwidth cost—
Cost per 1,000 requests—
Data transferred / month—
Requests per month—
Annual estimate—
Cost as traffic grows
What this endpoint costs if monthly volume doubles, 5x or 10x.
What the REST API Cost Calculator does
REST is the most common API style, where each endpoint maps to a resource and clients make one HTTP request per action. Because REST is request oriented, its cost scales cleanly with the number of calls, plus the bandwidth of the JSON responses. Managed REST gateways often price around $3.50 per million requests, which is the default here.
This REST API cost calculator combines the per request gateway fee with bandwidth from your average response size to give a monthly total. REST APIs can be chatty, since fetching related data often means several round trips, so watch how call volume adds up across a typical user session.
Heads up on pricing. The rates built into this tool are public list estimates for July 2026 and can change without notice. Providers also offer batch discounts, prompt caching and volume tiers that lower real costs, so treat the output as a planning estimate, not a quote.
The formula
request cost = requests ÷ 1,000,000 × price per million
bandwidth = requests × avg KB ÷ 1,000,000 × egress price
total = request cost + bandwidth
bandwidth = requests × avg KB ÷ 1,000,000 × egress price
total = request cost + bandwidth
Worked example
For 5,000,000 REST requests a month at $3.50 per million with 40 KB responses at $0.09 per GB, request cost is 5 × $3.50 = $17.50 and bandwidth is 200 GB × $0.09 = $18, for about $35.50 a month.
Ways to lower your API and backend costs
- Serve responses through a CDN. Cached, edge-delivered responses cut egress cost and take load off your origin.
- Compress payloads. gzip or brotli plus trimming unused JSON fields reduces bandwidth on every single request.
- Cache common responses. Avoid recomputing identical results for repeated reads, which lowers both compute and request fees.
- Reduce chatty designs. Combine several small calls into one batch endpoint or a single GraphQL query to cut request volume.
- Right size and autoscale. Match capacity to real peak traffic instead of paying for servers that sit idle most of the day.
Frequently asked questions
How much does a REST API cost to run?
Managed REST gateways cost around $3.50 per million requests plus bandwidth. A few million requests a month typically runs tens of dollars. Enter your volume above.
Why can REST be chatty?
Because each resource is a separate endpoint, loading a screen often needs several requests. That raises call volume compared with a single aggregated query.
Is GraphQL cheaper than REST?
GraphQL can reduce round trips by fetching exactly what a screen needs in one request, but each query costs more compute. Compare with the GraphQL cost calculator.
How do I lower REST API costs?
Cache common GET responses, use an HTTP gateway instead of REST where features allow, compress payloads, and combine chatty calls into batch endpoints.
Are these rates accurate?
They are 2026 estimates. Confirm your gateway and egress rates for an exact figure.