What is the CASC Score?

Outlining the APImetrics performance scoring system

Key Concepts

The CASC (Cloud API Service Consistency) score is a simple, easy to understand credit rating-like metric that blends together a number of metrics for each API (including availability, latency and number of outliers) using proprietary machine learning technology benchmarked against APImetrics unrivalled dataset of historical API test call results to give a single number between 0 and 999 that indicates the relative quality of the API over a given period. The CASC score allows you at a glance to see the quality of an API, whether it is getting better or worse and how it compares to other APIs.


Scores are generated on a weekly (Monday-Sunday) and calendar month basis.

What does a score mean?


Over 800

You'll have few issues with your API, indicating things are generally doing well.


Between 600-800

The API is performing below average, with significant performance periods where users are impacted.


Below 600

Unacceptable performance from the API leading to significant performance issues impacting users.

Insights Reporting

The Monthly Insights Ranking can be invoked by clicking on the insights button in the Insights button in the ANALYTICS section on the left side of each page.



See at a glance how well the quality of an API

You can compare instantly compare the quality of different API in a particular period.

Click on the name of the test to invoke the Insights report for the test.


You can scroll down to see more information about the performance of the API.


You can see how the API is performing in different regions and from different clouds.


Outliers are calls with latencies much longer than the median. Outliers often indicate that there are performance issues with the API.


Outliers clustered together can be a sign that the quality of API is below expectations.