Best 10 Tools for Debugging APIs in 2025

SoapUI is a testing platform that checks how APIs and web services perform. You can use it to send requests to your API, check the responses, and make sure everything works as expected. It runs on Windows, Mac, and Linux computers because it is built using Java.

Apidog is a platform that handles the complete process of creating and managing APIs. You can design your API structure, test how it works, create clear documentation, and share it with your team, all from one application.

Thunder Client is a REST API testing tool that lives inside Visual Studio Code. You can send requests, check responses, and organize your API tests without opening another program. It works just like other API testing tools but runs directly in your code editor.

HTTPie is a tool designed for testing APIs and HTTP servers with an easy-to-understand approach. You type commands that look similar to the actual HTTP requests you want to make, and HTTPie handles the technical details for you. The responses come back formatted with colors, making JSON and other data easy to read.

Paw is a complete API testing and development tool designed for Mac computers. You can use it to create and send HTTP requests, then see detailed responses with headers, status codes, and body content. The app supports all common HTTP methods including GET, POST, PUT, DELETE, and PATCH.

Insomnia is a desktop application that lets you test and work with APIs. Think of it as a specialized tool for developers who need to send requests to APIs and check the responses they get back. It supports all major API types, so you don't need different tools for different projects.

Katalon is a complete testing solution that automates the process of checking if software works correctly. Instead of testing applications manually every time, Katalon lets you create automated tests that run on their own.

Bruno is an "offline-first API client" that revolutionizes how developers test and manage APIs. Instead of forcing you to create accounts or store data in the cloud, Bruno saves everything directly on your device using a simple text format called "Bru."

Hoppscotch is an API development environment that runs in your web browser. You can test any API by sending requests and viewing the responses instantly. Unlike traditional tools, Hoppscotch is completely free and open-source, meaning anyone can use it or even contribute to improving it.

Postman is an all-in-one platform for working with APIs throughout their entire lifecycle. It provides tools to send API requests, view responses, write tests, create documentation, and monitor performance. Unlike basic HTTP clients, Postman offers a complete environment where teams can organize their work into collections, share them with teammates, and automate testing.