Most teams focus on functional correctness in API testing—making sure endpoints return the right response. But in real-world applications, performance and scalability matter just as much. An API that works correctly under light usage can fail under peak traffic, leading to slow response times or even outages.
Here are key aspects of performance and scalability testing for APIs:
Load Testing – Measure how your API behaves under expected user traffic. This helps validate SLAs like response time and throughput.
Stress Testing – Push the API beyond normal limits to see when it breaks. This exposes bottlenecks such as database locks or thread pool exhaustion.
Spike Testing – Simulate sudden surges in traffic (e.g., flash sales or viral events) to check if your API can recover gracefully.
Endurance Testing – Run the API under continuous heavy load to detect memory leaks or resource exhaustion.
Scalability Validation – Test how your API performs when infrastructure scales horizontally (e.g., adding more servers or containers).
By extending
api testing
to cover these performance aspects, teams can ensure their systems not only function but also scale reliably under real-world demands. This approach reduces downtime, improves user experience, and builds trust in production environments.
