Top 20 Online Postman-Like Tools for API Testing and Debugging

Looking for Postman alternatives? Explore 20 online tools for API testing and debugging, including Apidog, Hoppscotch, and more. Perfect for developers and testers!

Oliver Kingsley

Oliver Kingsley

14 May 2025

Top 20 Online Postman-Like Tools for API Testing and Debugging

In the rapidly evolving world of software development, API testing has become a cornerstone for ensuring seamless integration and functionality. APIs (Application Programming Interfaces) act as the bridge between different software systems, enabling them to communicate and share data. As APIs grow in complexity, the need for robust API testing tools has never been greater.

While Postman has long been the go-to tool for API testing, many developers are now seeking Postman alternatives that offer similar or even enhanced features. Online API testing tools provide flexibility, collaboration, and ease of use, making them ideal for modern development workflows. Whether you're looking for a Postman replacement or simply exploring new options, this article delves into the top 20 online Postman-like tools for API testing and debugging.

Why Choose Online API Testing Tools?

Before diving into the list, let’s explore why online API testing tools are gaining popularity:

Top 20 Postman-like Tools for Testing API Online

Here’s a comprehensive list of the best online API testing tools that can serve as excellent Postman alternatives:

1. Apidog

Apidog is an all-in-one API development tool that combines API testing, debugging, mocking, design and documentation in a single platform. It supports REST, GraphQL, and WebSocket APIs, making it a versatile choice for developers.

Testing APIs Online Now!

Apidog: The All-in-One API Workflow Automation Tool

Key Features:

sending API request using Apidog
Managing environment at Apidog
What is Apidog MCP Server?
Apidog MCP Server creates a seamless connection between your API documentation and AI coding assistants, enabling developers to leverage AI for more efficient API development without constant context switching.

Apidog stands out as a Postman replacement due to its comprehensive feature set and user-friendly interface.

💡
Pro tip: Finding Postman alternative with unlimited collection runner, check out these top tools.

2. Hoppscotch

Hoppscotch is an open-source, fast, and efficient API development tool that runs directly in your browser. It is ideal for developers who want quick, distraction-free API testing without extensive setup, supporting REST, GraphQL, and WebSocket protocols.

The Lightweight, Speed-Focused API Tester

Key Features:

API testing using Hoppscotch

Hoppscotch’s speed-focused design is perfect for developers working on small to medium projects who need to test APIs across various protocols quickly.

3. ReqBin

ReqBin provides a seamless online environment for testing APIs without needing to download any software. It's a perfect choice for quick API requests and debugging.

Online API testing tool — ReqBin

Key Features:

4. Beeceptor

Beeceptor is a simple yet powerful API testing tool that lets users create custom endpoints. It is particularly useful for testing and mocking APIs before they are fully developed.

Using Beeceptor for API testing and mocking

Key Features:

Beeceptor is perfect for API developers who need to test APIs in isolation before integrating them into production environments.

5. Swagger Hub

Swagger Hub offers a comprehensive suite for designing, documenting, and testing APIs. It integrates well with Swagger/OpenAPI standards, making it a great choice for teams focused on specification-driven development.

using Swagger Hub for API testing

Key Features:

Swagger Hub is ideal for teams needing robust API design, documentation, and testing.

6. Firecamp

Firecamp is a powerful tool that aims to simplify API testing with its intuitive UI. It provides support for REST, GraphQL, and WebSockets, making it a versatile option for various testing needs.

Firecamp — an open-source Postman alternative

Key Features:

Firecamp is an excellent choice for users looking for a unified API testing and debugging environment that supports multiple protocols.

7. HTTPie Online

For developers who prefer simplicity, HTTPie Online provides a minimalist interface for testing APIs. Its clean design focuses on delivering a streamlined experience with all the essential features.

API testing using HTTPie Online

Key Features:

HTTPie Online is perfect for developers who value simplicity and speed in their API testing process.

8. Stoplight

Stoplight is an API platform focused on design-first development, allowing users to create, test, and mock APIs effectively.

API testing using Stoplight

Key Features:

Stoplight is perfect for teams that emphasize API design-first approaches in their development workflow.

9. Apiary

Apiary provides a robust environment for designing, testing, and monitoring APIs. It’s especially useful for teams working with OpenAPI specifications.

Using Apiary for API testing

Key Features:

Apiary is an excellent option for managing the entire API lifecycle, from design to deployment.

10. Assertible

Assertible is an automated API testing tool that focuses on simplifying continuous testing for your APIs. It’s designed to work seamlessly with CI/CD pipelines.

Using Assertible for API testing

Key Features:

Assertible is ideal for continuous integration testing, allowing developers to automate their testing and debugging processes.

11. ExtendsClass API Tester

ExtendsClass is a straightforward online API tester that helps users perform quick and easy HTTP request testing.

Using ExtendsClass API Tester to test APIs

Key Features:

If you're looking for a simple yet efficient tool for basic API testing, ExtendsClass provides just what you need.

12. Apipheny

Apipheny is a unique tool that connects Google Sheets to APIs for easy data retrieval and manipulation.

Using Apipheny to test APIs

Key Features:

Apipheny is ideal for users who need to integrate APIs with Google Sheets without writing code.

13. Telerik Fiddler Everywhere

Fiddler Everywhere offers powerful API debugging capabilities that allow developers to inspect HTTP requests and responses in detail.

Using Telerik Fiddler Everywhere for API testing

Key Features:

Fiddler Everywhere is perfect for developers looking for advanced API debugging capabilities.

14. RESTtest

RESTtest is an easy-to-use tool for testing REST APIs. It allows users to execute simple HTTP requests and analyze responses.

Using RESTtest to test APIs

Key Features:

For those who need a straightforward API testing solution, RESTtest is a great option.

15. JSONPlaceholder

JSONPlaceholder is a fake online REST API used for testing and prototyping.

Using JSONPlaceholder to test APIs

Key Features:

JSONPlaceholder is ideal for developers who need a quick and reliable mock API for their testing needs.

16. Mocklets

Mocklets provides an easy way to create mock APIs for testing and development purposes.

Using Mocklets to test APIs

Key Features:

Mocklets is an excellent tool for developers who need mock APIs for front-end or integration testing.

17. Reqres

Reqres provides a fake API that can be used for front-end testing and prototyping.

Using Reqres to test APIs

Key Features:

Reqres is perfect for front-end developers who need a quick API for testing.

18. API Context

API Context is a real-time API testing and debugging platform that provides instant feedback on API responses.

Using APIContext to test APIs

Key Features:

API Context is an excellent choice for developers looking for real-time testing capabilities.

19. BlazeMeter

BlazeMeter is designed for performance and load testing APIs, ensuring that they can handle large-scale traffic.

Using BlazeMeter to test APIs

Key Features:

BlazeMeter is ideal for users who need to ensure their APIs are performance-ready under load.

20. API Fortress

API Fortress offers continuous API testing with integration into CI/CD pipelines.

Using API Fortress to test APIs

Key Features:

API Fortress is perfect for automating and scaling API testing throughout the development lifecycle.

Conclusion

Choosing the right online API testing tool can significantly enhance your development workflow. Whether you’re looking for a Postman replacement or simply exploring new options, the tools listed above offer a wide range of features to meet your needs.

Apidog stands out as an all-in-one solution for API development, testing, and debugging. Its comprehensive feature set and user-friendly interface make it a top choice for developers worldwide.

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