There are several popular and widely-used test automation frameworks for API testing, each with its own strengths and features. The choice of the best framework depends on your specific requirements, project constraints, programming language preferences, and team expertise. Here are some notable test automation frameworks for API testing:

1. Postman: Postman is a widely-used and versatile API testing framework that offers a user-friendly interface for designing, executing, and automating API tests. It provides features such as request building, response validation, test scripting, and test report generation.

2. REST Assured: REST Assured is a Java-based framework specifically designed for testing RESTful APIs. It offers a simple and intuitive syntax, supports various authentication mechanisms, and provides powerful assertions for validating API responses.

3. Karate: Karate is an open-source framework built on top of Cucumber and Gatling, making it ideal for API testing and performance testing. It allows writing API tests in a BDD-style (Behavior-Driven Development) format and provides features like request/response validation, data-driven testing, and reporting.

These frameworks provide different levels of flexibility, ease of use, and integrations. Consider your project requirements, programming language familiarity, community support, and available resources to select the framework that best suits your needs. If you want to know more about test frameworks, check out this blog.