Karate vs SuperTest

Free tier available

Free and open source

Open source core; Karate Labs sells a commercial IDE and enterprise support separately.

Free and open source. You pay in engineering time and CI minutes.

The open-source framework is complete and free.

Everything, self-hosted

Widely used

Karate Labs · since 2017

Widely used

OSS community · since 2014

• One DSL covers functional API tests, mocks and load tests — rare consolidation.
• Powerful JSON matching that removes most assertion boilerplate.
• Non-Java testers can write meaningful tests.

• Fast: no network, no separate server process, no port conflicts in CI.
• Tiny API you can learn in ten minutes.
• Works with whichever runner you already use.

• The custom DSL is another language to learn and cannot be refactored by an IDE.
• Debugging complex scenarios is harder than in plain code.
• The UI automation feature is far behind dedicated browser tools.

• Node.js only, and only for services you host yourself.
• In-process testing skips the real network stack, proxies and load balancer.
• No environment management or collection concept for cross-service flows.

Teams wanting API testing and mocking in one tool, including non-Java testers.

Node.js API projects testing their own routes in the unit/integration layer.