KPIs for APIs – Reporting on Key Performance Indicators 2018-04-10T04:14:32+00:00

KPIs for APIs

There are multiple options for measuring API performance.

How do you choose?

Critical Key Performance Indicators

Total API Call Latency
TCP Connect TIme
Measured Pass Rate
Actual Passrate



There are lots of things that can be measured with an API:

  • Pass Rate – based on HTTP codes
  • Pass Rate – based on functional reporting. Did the API do what you wanted it to?
  • Latency – even plus location: Network, Server, Infrastructure
  • Overall Service Quality – how consistent are your results?
  • Geographic Performance

Multiple ways to measure APIs and the impact they may have on your services, customers and critical interdependencies. But outside of what you can measure with your current products.

Let us show you a demo of how we measure APIs

Get Started

Measured Pass Rate

Web API Performance Testing API Monitor API Speed Test API Speed Test API Test Online API Test Online API Speed Test API Test Online Monitor REST API REST API Monitoring API Monitoring Tools REST API Monitoring REST API Performance Web API Performance Testing Web API Performance Testing API Testing Service

The pass rate is the actual measured success rate for an API call from a specific location.

But APIs can pass at different rates from different locations. So don’t just assume that HTTP-200 means ‘All OK’. Just because your API gateway or APM stack logs show 200 codes doesn’t mean that everything is working well – or even at all.

Effective Pass Rate

KPI SLA and Pass Rate

It’s entirely possible to have two APIs doing the same thing, but with wildly different effective pass rates.

Even with a 100% pass rate, there may be events and performance issues that cause timeouts and other problems. You need to take into account the performance, including latencies and items that may affect end users.

Latency, Cloud and Geographic Factors

API Location KPI

Latency is complex for APIs. Using a common ‘ping’ tool won’t tell you what you need to know. API calls include multiple steps:

  • Connect Time
  • DNS Look Up
  • Server Side Processing Time
  • Internet Travel Time
  • Total Call Time

And each of these vary by geography. You need careful analysis to measure an API call.

See Live API Latency

Why compromise?

APImetrics CASC Score Ranks

A slow API might not be a problem. But an API that is slow only sometimes might well be. Systems measuring average performance can miss significant performance issues lasting many hours.

This is why APImetrics uses CASC (Cloud API Service Consistency) scoring. It’s like-for-like comparisons between different APIs that show performance as a single, 3-digit score.

Sign up for API Rating Reports

Join the engineers, managers and executives using APImetrics today

Get Started for Free Today