Effective Strategies 10 min read

9 Best Postman Alternatives (Open Source)

In this article, we'll explore Postman alternatives, their features, advantages, and disadvantages. You'll have a better understanding of the top options and choose the best tool for your API development needs.

Top 9 Postman Alternatives (Open Source)

Numerous developers use Postman to test your API, which is a widely recognized tool in the software development industry. With its user-friendly interface and powerful testing capabilities, Postman has become a popular tool for developers to ensure the functionality and reliability of their APIs. However, there are many free alternatives on the market.


In this article, we'll delve deeper into 9 open-source Postman alternatives to provide you with a comprehensive overview of their features, advantages, and disadvantages.

Top 1. Apidog

Web site: Apidog

Compared to Postman, Apidog is the best alternative API tool. It is an All-in-One API tool for API design, documentation, debugging, mock, and test.  With Apidog, you can design and debug APIs faster and more efficiently, while generating documentation, mock data, and tests automatically.

Apidog Interface

In addition, Apidog is an open-source alternative to Postman that functions as a Chrome extension for API testing and documentation. It offers a platform for developers to manage their APIs efficiently. Similar to Postman, Apidog allows users to make API requests, inspect responses, and organize requests into collections. It also enables users to create detailed API documentation, making it easier to share and collaborate on API-related projects. The extension's open-source nature and Chrome integration make it a versatile choice for developers seeking a Postman alternative for testing and managing APIs.

The Key Features of Apidog:

Apidog is a versatile toolkit that covers the entire API creation process. It's like a Swiss Army knife for APIs, helping with design, testing, and more. Here's what Apidog offers:

  • Design and Debugging: Apidog lets you design and debug APIs visually, with support for JSON Schema.
  • Automated Testing: It can generate tests, validate responses, and help with continuous integration. It can automate tasks and keep your API definitions in sync.
  • Documentation: Apidog can generate beautiful documentation for your APIs.
  • Mocking Data: It can create mock data, making testing easier. What Apidog Offers for GraphQL Testing: Apidog works well for testing GraphQL APIs too. It has features like:
  • Integration with other tools: Apidog integrates with a range of other tools and platforms, including Jenkins and GitHub, which provides flexibility and choice for developers.
  • Easy to use: Apidog with clear navigation is easy for beginners to get started with due to its low entry barrier.
  • Support various devices: Apidog can be used on Windows, Mac, and Linux operating systems, as well as with Chrome and Edge extensions.


  • Cost: ¬†Apidog offers a free version with no time limit, you can use all the features of the professional version for free. However, its more advanced team management features are only available with a paid subscription.
Apidog - An integrated platform for API design, debugging, development, mock, and testing
Choose the appropriate Apidog plan according to your needs to work more efficiently.

Top 2. Swagger UI

Web site: Swagger UI

Swagger UI is an open-source Postman alternative tool for API design, documentation, and testing.

Swagger UI

Here are some of the advantages and disadvantages of using Swagger UI below, as well as you can check it for detail.

What is Swagger API? A Complete Guide for Beginners
Swagger simplifies the process of creating and maintaining API documentation through a user-friendly interface and various features.

Pros of Swagger UI:

  • Interactive documentation: Swagger UI generates interactive documentation for APIs, which can be easily shared with stakeholders to provide a clear understanding of the API's capabilities and uses cases.
  • API testing: Swagger UI allows developers to test their APIs directly from the documentation page, which can help identify any issues or errors in the API.

Cons of Swagger UI:

  • Limited functionality: Swagger UI is primarily a documentation tool, and its testing capabilities may be limited compared to dedicated API testing tools.
  • Limited customization: The tool has limited customization options, which may be a disadvantage for developers who require more control over the look and feel of their API documentation.

Top 3. Insomnia REST Client

Web site: Insomnia REST Client

Insomnia is a popular alternative to Postman. It's an open-source API client that allows you to design and test your APIs. Insomnia Rest Client provides a sleek and intuitive interface that makes it easy to organize your API requests and responses. It also offers a range of features, including code generation, OAuth authentication, and automatic cookie management.


If you don't know the difference between Insomnia and Postman, here is a good guide.

Postman vs Insomnia: Which API Testing Tool is Right for You
In this post, we will compare the features and functionality of Postman and Insomnia, as well as their pros and cons, to help you choose the right API testing tool for your needs.

Pros of Insomnia:

  • Insomnia is a cross-platform tool, which means it can be used on Windows, Mac, and Linux operating systems.
  • The user interface of Insomnia is user-friendly and easy to navigate, which makes it ideal for both technical and non-technical users.
  • Insomnia offers code snippets for API requests in multiple programming languages, including JavaScript, Python, and Ruby.
  • The tool also supports environment variables, which enables users to manage complex testing scenarios easily.
  • Insomnia supports collaboration features, allowing team members to work together on API development projects.
  • It can be automated using scripts, making it easy to integrate API testing into continuous integration and deployment (CI/CD) workflows.

Cons of Insomnia:

  • While Insomnia is generally fast and responsive, it may encounter performance issues when working with large or complex APIs.
  • Although it is a free and open-source tool, some of the advanced features may require a paid subscription.
  • The tool may not have all of the features that some users may require for API development and testing.

Top 4. Paw

Web site: Paw

Paw is a powerful API testing and development tool for Mac. It provides a range of features, including code generation, automatic validation, and dynamic values. One of its standout features is the ability to generate client code in multiple languages.


Pros of Paw:

  • Code generation: Paw offers a code generation feature that generates client code in multiple languages, making it easier to integrate APIs with different programming languages.
  • Dynamic values: Paw provides a dynamic value feature that allows developers to create custom values that can be used in requests and responses.
  • Automatic validation: Paw automatically validates requests and responses, ensuring that APIs are functioning correctly.
  • Advanced features: Paw offers advanced features such as OAuth authentication, support for scripting languages, and automatic cookie management.

Cons of Paw:

  • Only available for Mac: Paw is only available for Mac users, which limits its accessibility for developers using other operating systems.
  • Cost: Paw offers a free trial, but the full version can be costly for individual developers or small teams.
  • Limited support for Swagger and RAML: Paw has limited support for Swagger and RAML, which may not be ideal for developers who heavily rely on these API design standards.

Top 5. Apigee

Web site: Apigee

Apigee is an API management platform that offers a range of tools and features to help organizations design, develop, secure, and manage APIs.


Here are some advantages and disadvantages of using Apigee:

Pros of Apigee:

  • Scalability: Apigee can handle large volumes of API traffic, making it suitable for enterprises and organizations with high traffic and complex API requirements.
  • Multi-cloud support: Apigee can be deployed in multiple cloud environments, including Amazon Web Services, Microsoft Azure, and Google Cloud, which provides flexibility and choice for organizations.
  • Developer-friendly: Apigee offers a range of developer tools and resources, including a developer portal, documentation, and API testing tools, to help developers build and test APIs.

Cons of Apigee:

  • Cost: Apigee can be expensive for small organizations or those with limited API usage.
  • Complexity: The platform can be complex, and its steep learning curve can make it difficult for less experienced developers to use it effectively.
  • Support: Some users have reported issues with Apigee's customer support, specifically regarding response time and quality.

Top 6. SoapUI

Web site: SoapUI

SoapUI is another Postman alternative API testing tool that allows you to test both REST and SOAP APIs. It provides a range of features, including testing, mocking, and security testing. SoapUI also offers an intuitive and user-friendly interface that makes it easy to design and test your APIs.


Pros of SoapUI:

  • SoapUI is a popular API testing tool that supports both REST and SOAP API.
  • SoapUI offers a user-friendly interface for creating and executing test cases, making it easy for both technical and non-technical users to use.
  • The tool supports multiple protocols and data formats, making it easy to test APIs across different platforms and technologies.
  • SoapUI offers integration with popular development tools such as Eclipse and IntelliJ IDEA, allowing developers to seamlessly incorporate API testing into their development workflows.

Cons of SoapUI:

  • SoapUI can be resource-intensive, and its performance may suffer when testing large or complex APIs.
  • The user interface can be overwhelming for new users, and it may take some time to learn how to use all of the features effectively.
  • Some users have reported issues with the tool's stability and occasional crashes, particularly when working with large datasets or complex test cases.

Top 7. Runscope

Web site: Runscope

Runscope is a cloud-based API testing and monitoring tool. It allows you to test and monitor your APIs from multiple locations around the world. Runscope provides a range of features, including automatic test generation, webhook testing, and API debugging. It also offers a range of integrations, including Slack, PagerDuty, and HipChat.


Here are some advantages and disadvantages of Runscope:

Pros of Runscope:

  • Runscope is easy to use and offers a user-friendly interface.
  • The tool provides a variety of testing and monitoring options, including automation, real-time monitoring, and integration with other popular tools.
  • Runscope offers advanced features, such as scriptable tests and request chaining, that allow for more complex testing scenarios.
  • The tool can be deployed either in the cloud or on-premise, depending on the organization's needs.

Cons of Runscope:

  • Some users have reported that Runscope can be complex to set up and configure, which may be a barrier for some developers.
  • The tool may not be as intuitive as other API testing tools, which could lead to a steeper learning curve.
  • The pricing model for Runscope may not be ideal for all organizations, particularly for those with smaller budgets.

Top 8. Boomi

Web site: Boomi

Boomi is a cloud-based integration platform that offers solutions for integrating data and applications. It allows users to create integrations without the need for extensive coding, using a low-code platform.


Pros of Boomi:

  • Cloud-based: Being cloud-based, Boomi offers scalability and flexibility, as well as easy access to data from anywhere.
  • Wide range of connectors: Boomi has a large library of connectors, allowing it to integrate with a wide variety of applications and systems.
  • Low-code platform: Boomi's low-code platform allows for rapid development and deployment of integrations, reducing the need for extensive coding.
  • Strong security features: Boomi offers robust security features, including encryption, access control, and compliance with various regulations.

Cons of Boomi:

  • Cost: Boomi can be expensive, especially for small businesses or individuals. The pricing structure is based on usage, which can add up quickly for organizations with high integration needs.
  • Limited customization: Boomi's low-code platform may not allow for as much customization as some organizations require, especially if they have specific integration needs.
  • Reliance on Internet connectivity: Being cloud-based, Boomi is dependent on Internet connectivity. Any disruptions or downtime can impact the availability of data and integrations.

Top 9. Restlet Studio

Restlet Studio is a web-based API design and testing tool. It provides a range of features, including API design, testing, and documentation. Restlet Studio also offers an intuitive and user-friendly interface that makes it easy to organize your API requests and responses. It also offers a range of integrations, including GitHub, Swagger, and RAML.

Restlet Studio

Here are some of the key features and benefits of Restlet Studio:

Pros of Restlet Studio:

  • Comprehensive feature set: Restlet Studio offers a range of features, including support for various API types and methods, code generation, and documentation tools, which can help streamline the API development process.
  • Collaboration tools: Restlet Studio supports collaboration and teamwork by enabling team members to work on API development and testing projects together.
  • Cloud-based and Lightweight: Being a cloud-based tool, Restlet Studio offers the advantage of easy accessibility from any location and device with an internet connection.

Cons of Restlet Studio:

  • Limited functionality: Restlet Studio's free version has certain limitations, such as fewer API calls per day and limited storage space.
  • Pricing: The pricing of Restlet Studio can be a bit expensive for smaller teams and organizations.
  • Steep learning curve: While the interface is user-friendly, the tool can be complex, which can lead to a steeper learning curve for less experienced developers.


Postman is a popular API development tool, but there are plenty of alternatives on the market. Whether you're looking for a tool with a sleek interface, code generation capabilities, or cloud-based testing, there's an API testing and development tool out there for you. Apidog is the best ideal Postman alternative tool for you. Try it now.

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