Performance testing

Load testing measures how an API performs when many virtual users send requests at once. It shows response times, throughput, and errors as traffic increases, so you can find bottlenecks before your users do. With Postman, you can reuse your existing collections, run quick smoke tests locally, and scale to hundreds or more virtual users using managed cloud infrastructure.

Functional tests verify that your API behaves as expected, but they don’t tell you how it performs under heavy traffic. An API can pass functional tests and still experience slow response times or errors when many users make requests simultaneously. Postman lets you reuse your existing collections, scripts, and assertions for performance testing without maintaining a separate set of load-test scripts.

Start with an existing Postman collection and configure your virtual users, test duration, and load profile. Run the test in the Postman app or with the Postman CLI. For larger tests, use Postman Cloud to generate load from managed infrastructure, while Postman aggregates metrics such as response times, throughput, and errors into a single report.

Local tests are useful for validating a test setup and catching obvious performance issues, but your machine’s CPU, network, and other resource limits can affect results. Postman Cloud uses managed infrastructure to generate load at greater scale, with aggregated results and shared run history. You can use the same collection and test configuration without rewriting your test.

For more details, read Cloud Performance Testing with Postman: From Laptop to CI.

Yes. With Postman’s plugin, your coding agent can help configure and run performance tests using your existing Postman collections. Ask it to set the load profile, virtual users, and test duration, then run the test locally or in Postman Cloud. You can review the results to understand response times, throughput, and errors under load.

Yes. Use the Postman CLI to run performance tests in your CI/CD pipeline. Add --runner postman-cloud to run load tests on Postman Cloud and generate larger loads with more virtual users. Use --pass-if to set performance thresholds for supported metrics such as latency, error rate, or throughput.

Use Postman static IP egress to run cloud performance tests against beta and staging APIs protected by a firewall. Your security team can allowlist Postman’s fixed egress IP address so Postman Cloud can reach your API.