soapUI

vs

Apache JMeter

With Insomnia you can design, debug and deploy APIs. Insomnia is free API design platform and REST Client developed for macOS, Linux and Window. The application makes it easy to create and group requests, specify environment variables, authentication and generate code snippets. You can also get all the details on responses. View the whole request timeline, status codes, body, headers, cookies and much more. The software also makes it easy to orginize your projects with workspaces, folders, environments, drag-and-drop requests, and easily import and export your data. Insomnia integrates with API gateways such as the Kong API Gateway, and Kong for Kubernetes. While Insomnia comes with a free-forever license, the software provides premium monthly subscriptions for E2EE data sync and advanced collaboration features.

Postman simplifies each step of building an API and streamline collaboration so you can create better APIs. The software is a free API client that can send REST, SOAP, and GraphQL that allows you to design and mock APIs. Postman also provides premium features for subscribers that allows for better collaboration among teams where workspace can be setup to work closer together on your APIs and web services.

Katalon Studio is an automation testing tool that supports native plugins for the most popular CI tools: Jenkins, Bamboo, Azure DevOps, CircleCI, TeamCity, and more. Katalon Studio is built for continuous testing and integrates with your ecosystem with ease. Allowing you to run Web, API, mobile, and desktop test automation and deploy on Windows, macOS, and Linux.

Locust is a modern load testing framework an open source load testing tool written in Python. With Locust it's super simple to load test any form of web application or website, regardless of language, framework or type. Allowing you to define user behaviour with Python code, and swarm your system with millions of simultaneous users.