Top 15 Postman Alternatives for API Testing in 2026

15 Best Postman Alternatives

There are numerous Postman alternatives available that provide robust API testing and development features, offering various functionalities such as automation, security testing, and performance analysis.

1. TestMu AI KaneAI

TestMu AI KaneAI is an AI testing agent designed to enhance the API testing process. By using Natural Language Processing (NLP), KaneAI enables users to write test cases in plain English, reducing the complexity of API test creation. It integrates seamlessly into development pipelines and offers extensive support for multiple HTTP methods.

Features:

• Natural language test creation: Easily create test cases by describing them in plain English, making it accessible for both technical and non-technical users.
• Supports multiple HTTP methods: Allows you to test all major HTTP methods like GET, POST, PUT, DELETE, and PATCH.
• Curl command integration: Input curl commands directly and KaneAI automatically populates the required details, simplifying integration.
• Batch API testing: Test multiple APIs simultaneously, saving time when validating several endpoints.
• Dynamic variable support: Use variables within API bodies for flexible testing with varying data inputs.

2. Postcode

Postcode is a lightweight VS Code extension primarily designed for sending HTTP requests and performing quick API testing. It’s ideal for developers who need to validate APIs without dealing with complex setup or configurations. Postcode offers a simple and fast interface for testing RESTful APIs, making it one of the postman alternatives that streamline the testing process.

Features:

• Quick setup: No configuration needed, perfect for developers who need fast API testing without a setup.
• Supports RESTful APIs: Focuses on testing REST APIs, the most common API format used in modern applications.
• Lightweight interface: Offers a simple, user-friendly design for quick validation.
• Ideal for solo developers: Best for small-scale testing projects or individual developers who need speed over advanced features.

3. Firecamp

Firecamp is a comprehensive platform designed for collaborative API testing and development. It supports multiple protocols such as REST, GraphQL, and WebSocket, providing flexibility for developers working with various API technologies. It’s particularly valuable for teams that need real-time collaboration.

Features:

• Supports multiple protocols: Includes support for REST, GraphQL, and WebSocket APIs, making it versatile for diverse testing needs.
• Real-time collaboration: Teams can collaborate in real time while working on the same API collections.
• Advanced API monitoring: Keeps track of API health with real-time monitoring, providing insights into performance.
• Seamless integration with development tools: Firecamp integrates well with existing development workflows to streamline API testing.

4. TestMace

TestMace is designed for comprehensive API testing, supporting performance, security, and functional testing. It’s built with teams in mind, offering collaboration features, real-time monitoring, and advanced reporting to ensure your APIs perform well in all conditions.

Features:

• Performance and security testing: Tests both performance (load testing) and security of your APIs to ensure they are robust.
• Real-time API monitoring: Provides insights into the health and status of your APIs during testing.
• Advanced reporting: Detailed reports and analytics to understand how your APIs are performing.
• Collaboration features: Supports team collaboration, making it ideal for distributed development teams.

5. Bruno

Bruno is a fast, privacy-focused, open-source API client. It allows users to store collections locally and integrates seamlessly with Git for version control. Ideal for developers who want a simple yet effective tool for quick API testing.

Features:

• Fast and lightweight: Optimized for speed, making it perfect for quick testing without the overhead of more complex tools.
• Local data storage: Data is stored locally, ensuring that sensitive information remains private.
• Git integration for version control: Easily manage API collections and keep them versioned through Git.
• Simple user interface: Offers a clean and intuitive interface for easy API testing without unnecessary complexity.

6. HTTPie

HTTPie is an open-source, command-line HTTP client that prioritizes simplicity and ease of use. It allows developers to send HTTP requests and view responses in a readable format. HTTPie is great for quick testing and debugging, especially for those who prefer working in the terminal.

Features:

• Simple and intuitive syntax: Makes API testing easy with a user-friendly command-line syntax.
• Supports multiple protocols: Works with HTTP, HTTPS, and WebSocket protocols.
• Lightweight and fast: A minimal tool for quick and efficient API tests.
• Readable output: Clear and formatted output for easier debugging and understanding of responses.

7. cURL

cURL is another open-source, command-line tool that supports transferring data over various protocols, including HTTP, HTTPS, FTP, and more. It’s commonly used for testing APIs and debugging network-related issues. cURL is highly flexible and is often integrated into scripts for automated testing.

Features:

• Supports numerous protocols: cURL works with HTTP, FTP, and many other protocols, making it highly versatile.
• Command-line tool: Offers terminal-based API testing, ideal for automation.
• Wide community support: cURL has a large user base, ensuring good documentation and resources.
• Easy script integration: Can be easily incorporated into automated scripts for continuous testing.

8. Swagger

Swagger is a suite of tools that helps developers design, document, and test APIs. With Swagger UI, which is an open-source tool, users can interact with APIs directly from their documentation, making it a popular choice for teams working on API design in addition to testing.

Features:

• API design and documentation tools: Swagger helps design and document APIs in a streamlined process.
• Interactive API documentation: With Swagger UI, users can test APIs directly from the documentation.
• Supports REST and GraphQL: Ideal for testing both RESTful and GraphQL APIs.
• Collaboration tools: Integrates with SwaggerHub for team collaboration and API versioning.

9. Hoppscotch

Hoppscotch is an open-source, web-based tool for API testing. It’s simple to use and supports REST, GraphQL, and WebSocket protocols. Hoppscotch’s minimalist design makes it fast and ideal for quick, no-frills testing, making it one of the top postman alternatives for developers seeking simplicity.

Features:

• Web-based, no installation required: No setup necessary, making it easy to get started right away.
• Supports REST, GraphQL, and WebSocket: Flexibility for different types of API testing.
• Open-source and free: Fully open-source and available for free.
• Simple and intuitive interface: Easy-to-use, minimalist design for faster API testing.

10. JMeter

Apache JMeter is a popular open-source tool for load and performance testing, but it also supports API testing. It allows users to simulate large numbers of API requests to check how APIs handle stress, making it ideal for testing scalability and performance.

Features:

• Excellent for load and performance testing: Simulate high traffic to test API performance under load.
• Highly customizable with plugins: Extend JMeter’s functionality with additional plugins.
• Free and open-source: No cost for using JMeter, and it’s community-driven.
• Supports both API and web testing: Versatile enough for testing various types of web services.

11. SoapUI

SoapUI is a comprehensive API testing tool, especially for SOAP and REST APIs. It is an open-source tool and it offers advanced testing capabilities like security, performance, and load testing. SoapUI is highly suitable for enterprise-level applications.

Features:

• Comprehensive security and load testing: Test APIs for security vulnerabilities and performance under load.
• Supports SOAP and REST APIs: Ideal for testing both SOAP and RESTful services.
• Detailed reporting and analytics: Track and analyze test results with comprehensive reports.
• Integrates with CI/CD tools: Supports automation and integration into continuous deployment pipelines.

12. ReadyAPI

ReadyAPI, an extension of SoapUI, offers advanced features for API testing, including security testing, performance testing, and automation. It’s a comprehensive solution for enterprise-level testing and integrates seamlessly with CI/CD workflows.

Features:

• Advanced API security and performance testing: Strong tools for security checks and load testing.
• CI/CD integration for automation: Easily integrate API tests into continuous testing workflows.
• Comprehensive API management: Covers the entire API lifecycle from design to testing.
• Enterprise-level features: Suitable for large teams with complex testing needs.

13. Assertible

Assertible is an automated API testing tool designed for continuous integration workflows. It integrates seamlessly with CI/CD systems to run API tests automatically, making it perfect for teams practicing continuous testing.

Features:

• Automated regression and integration testing: Automatically tests your APIs with every update.
• Easy integration with CI/CD pipelines: Seamlessly integrates into existing automated workflows.
• Real-time monitoring: Keeps track of your API’s health as it’s being tested.
• Clear reporting: Provides detailed test results and actionable insights.

14. Karate Labs

Karate Labs uses BDD syntax, making API testing easier. It supports functional, performance, and security testing. Its use of Gherkin syntax makes it easy for both technical and non-technical users to write tests.

Features:

• BDD-style syntax for easy test creation: Write tests in plain English with Gherkin syntax.
• Supports both functional and performance testing: Combines functional testing with performance testing.
• Open-source with community support: Free and backed by a strong community.
• API and UI testing: Tests both APIs and user interfaces in the same framework.

15. Tricentis Tosca

Tricentis Tosca is an enterprise-level test automation platform known for its model-based testing approach. It supports API, web, and mobile testing, and integrates well with CI/CD pipelines for automated testing.

Features:

• Model-based test automation: Create reusable test models for scalable testing.
• Supports API, web, and mobile testing: Comprehensive support for various test environments.
• Strong CI/CD integration: Easily integrates with continuous testing workflows.
• Enterprise-level solution: Ideal for large teams and complex testing projects.