Introduction

Implementing an API is a useful method for adding unique functionality to a web or mobile application without having to completely redesign it. It prevents tedious development effort that would have taken hours and ensures seamless integration of third-party services across all kinds of web interfaces. Application programming interfaces (APIs) have grown in popularity in web application development for this and numerous other reasons.

Application programming interfaces (APIs) are tested as part of the software testing process to see if they function as intended. It can be carried out manually or automatically, and it frequently occurs in tandem with other testing techniques including functional and regression testing.

Why test API

Today, most software is built using the Agile methodology. This means that the software is developed in small increments, and each increment is tested before it is released. This is where API testing comes in. It is a crucial part of the software development lifecycle (SDLC). It is a process that ensures that the API is working as expected and that it is ready for use. It is also a way to ensure that the API is secure and that it can be used by the intended audience.

Testing API using these tools helps QAs and developers to:

• Test the API for functionality without having to build a front-end
• Maintain and improve the API performance without waiting to build the entire application
• Discover bugs and errors in the API within a short time.

Choosing API testing tools

There are many API testing tools available on the market. It can take forever to find the right one for your project. To help make the right choice, I have curated a few things to consider when choosing the best API testing tool.

• Interoperability: The tool should be able to work with different platforms and operating systems. It must have the ability to integrate the tool with a continuous integration pipeline
• API basic requirements: The tool should be able to test the API for functionality, performance, and security. It should also be able to support the majority of the HTTP requests and responses.
• Ease of use: The tool should be easy to use and have a user-friendly interface. This will help you save time and effort when testing your API.
• Cost: The tool should be affordable and have a free version. This will help you save money.
• Multi-tasking: The ability to run tests in asynchronous mode to speed up execution

With these in mind, I have curated a list of the best API testing tools for developers and testers. These tools are easy to use and have a wide range of features that will help you test your API.

Top 5 API testing tools

• API Tester API Tester is a Mobile app to test any type of API, i.e. REST, GraphQL, WebSocket, SOAP, JSON RPC, XML, HTTP, HTTPS. Now the world is changing rapidly, and working directly from the smartphone from anywhere in the world increases productivity and gives more mobility. This makes it easier and handy for QAs and developers to perform their API with ease. It has a Powerful GraphQl editor with full-scale experience: body editor with Queries, Mutations, Subscriptions and syntax support; variables editor, documentation. API tester is best known for its user-friendly interface, ease of use and ability to process any kind data encoding, i.e. Query params, URLEncoded params, FormData, raw data, send files from device storage, cloud, remote server. It is available on Apple Store and Google Play

Pricing: FREE

• Postman Postman is a collaboration platform for API development. It was introduced in the market in 2012 as a chrome browser extension. Not only is Postman used to test API, it is also a great tool for API documentation. It is a great tool for developers and testers. It has a wide range of features that will help you test your API. It is easy to use and has a user-friendly interface. It is available on all platforms and operating systems. It is well known for its free version. For additional features, you can upgrade to the paid version.

Pricing: FREE and paid versions available. $12 per user per month for the paid version

• Thunder Client Thunder client is a Hand-crafted lightweight Rest Client for Testing APIs. It is well adopted by developers since it's a VSCode extension and allows them to test their API right in their workspace without switching windows. It was designed for simplicity, easy to use UI, lightweight and scriptless testing. It comes handy and easy to use since millions of developers already use VScode.

Pricing: FREE

• Insomnia Developers and Testers like to use Insomnia because of it's streamlined API client. You can quickly and easily send REST, SOAP, GraphQL, and GRPC requests directly within Insomnia. It allows you to automate manual API tests and integrate with your CI/CD process to build out an API testing pipeline using Insomnia Unit Tests. Pricing: FREE

• SoapUI This headless functional testing tool is dedicated to API testing. It allows testing of web services REST and SOAP APIs with no stress. For developers and testers looking to accelerate their ability to deliver REST, SOAP, and GraphQL APIs. SoapUI Open Source is one of the simplest and easiest ways to begin your API testing journey. It is available on all platforms and operating systems. It is a paid tool. It has a free trial that you can use for 14 days. After that, you will have to upgrade to the paid version.

Pricing: FREE trial for 14 days. Trial

CONCLUSION

API testing plays an important role in software development. It is a good practice to write test cases for APIs. It helps to find bugs and issues in the API. It also helps to improve the quality of the API.

The needs of various testing teams vary. It's important to select an API testing tool —or set of tools— that matches your team's unique requirements. It can be challenging to find the one tool that can do it all, but it's important to adopt a tool set that meets the goals of your organization and increases income.

Happy Hacking!

Bentil here🚀
Which of the tools listed above do you use for API testing? You can also share your experience with the tools you use.
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