Best API Testing Tools in 2026 — page 2

Stoplight Prism

Choose Prism if you need a free, open-source server for mocking APIs, validating data, or checking a target API against its OpenAPI document.

Yaak

Yaak brings API requests and Git-oriented organization together in a desktop client with local data storage.

REST Assured

REST Assured offers a broad set of REST testing and validation modules at no cost under an open-source license.

Step CI

Step CI combines flexible API workflows with local and CI/CD execution. Teams should note the default anonymous CLI analytics setting and that the separate support plan is custom-priced.

Tavern

Tavern provides YAML-based API testing across several protocols, with reusable test data and multiple ways to run tests.

SuperTest

SuperTest provides HTTP request and response checks alongside access to SuperAgent methods. Developers using `.end()` should handle assertion errors in the callback so test failures are reported.

Parasoft SOAtest

SOAtest brings API and microservices testing, test maintenance, and CI/CD integrations into one product. Prospective users can request tailored pricing or take a 14-day guided trial.

ReadyAPI

ReadyAPI covers several API testing needs, with distinct plans for testing, performance, and virtualization.

RESTler