Postman

Postman has evolved from a simple Chrome extension into the ubiquitous platform for API development and testing, defining the category for many. It excels as an interactive environment for designing, debugging, and documenting APIs. Its core strength lies in the seamless workflow from manual exploration to automated testing via collections. The platform fosters collaboration through shared workspaces, making it ideal for teams.

While facing increased competition, its vast ecosystem (mock servers, monitors, private API network) and continuous innovation in areas like Flows for visual automation and API governance keep it at the forefront. It's ideal for developers, testers, and technical writers who need a unified tool for the entire API lifecycle, from initial design to production monitoring.