Skip to content
ENExplore Calculators

ADC API Gateway Throughput Calculator

Size an API gateway's request ceiling from per-request CPU cost, with uplifts for authentication, transformation and cache hits.

About ADC API Gateway Throughput Calculator

An API gateway spends a near-constant amount of CPU per request on parsing, routing and policy evaluation, so its ceiling is the available core-microseconds divided by that cost. Cache hits skip the upstream call and most of the policy chain, so they are blended in at a fraction of the full cost. JWT validation and body transformation together can double the per-request cost, which is why a gateway benchmarked with a pass-through route delivers half that number once real policies are attached.

Formula

ADC API Gateway Throughput

effective CPU = base CPU × auth uplift × transform uplift, blended so cache hits cost 15% of a full request; max rps = cores × 1,000,000 µs ÷ effective CPU.

baseUs
Routing and proxying cost, ×1.25 for token validation and ×1.4 for payload transformation
cachedShare
Fraction of requests answered without touching the upstream

Worked example

With the default values below, ADC API Gateway Throughput Calculator returns Maximum Sustainable Request Rate of 102,269. Change any input above and every figure here is recalculated in your browser.

Inputs used

Requests per secondaccepts 1–10,000,000 rps
12,000 rps
Average response payloadaccepts 0.1–100,000 KB
8 KB
Base CPU per requestaccepts 1–100,000 µs
120 µs
CPU cores availableaccepts 1–1,024 cores
16 cores
Validating a JWT or API key per request
Yes
Request/response transformation enabled
Yes
Responses served from the gateway cacheaccepts 0–100 %
30 %

Results

Maximum Sustainable Request Rate
102,269 rps
CPU Utilisation at the Given Rate
11.7%
Throughput
768.0 Mbps
Effective CPU per Request
156.5 µs
Headroom Before Saturation
90,269 rps

Step by step

  1. 1Values used
  2. 2ADC API Gateway Throughput
  3. 3Maximum Sustainable Request Rate= 102,269 rps
  4. 4CPU Utilisation at the Given Rate= 11.7
  5. 5Throughput= 768.0 Mbps
  6. 6Effective CPU per Request= 156.5 µs
  7. 7Headroom Before Saturation= 90,269 rps

Assumptions and limits

  • The result is derived only from the 7 inputs listed above. Anything not among them is not part of the calculation.
  • In particular, this calculator does not take inflation, tax or compounding frequency into account.
  • Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is ADC API Gateway Throughput calculated?

effective CPU = base CPU × auth uplift × transform uplift, blended so cache hits cost 15% of a full request; max rps = cores × 1,000,000 µs ÷ effective CPU. An API gateway spends a near-constant amount of CPU per request on parsing, routing and policy evaluation, so its ceiling is the available core-microseconds divided by that cost. Cache hits skip the upstream call and most of the policy chain, so they are blended in at a fraction of the full cost.

Why does ADC API Gateway Throughput matter?

JWT validation and body transformation together can double the per-request cost, which is why a gateway benchmarked with a pass-through route delivers half that number once real policies are attached.

What values do I need to enter?

This calculator takes 7 inputs: Requests per second, Average response payload, Base CPU per request, CPU cores available, Validating a JWT or API key per request, Request/response transformation enabled, Responses served from the gateway cache. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.

Related Calculators

ADC API Gateway Throughput Calculator | Calcrivo