With the increasing use of cloud applications and interconnected platforms, the importance of API testing has also increased. Many of the services that people most commonly use rely on multiple interconnected APIs, and even a single malfunctioning API can impact the performance of the entire service.

Therefore, to ensure that API performs as expected, it’s a must for the software developers to perform API tests.

While testing APIs, testers look out for their reliability, security, functionality, and performance. Testing APIs from this standpoint can help them discover and fix potential bugs before the user accesses the cloud service.

Every professional software tester will know that API testing is no walk in the park. But test data automation via API testing tools can ensure seamless and qualitative testing of APIs and backend application’s code.

Let’s take a look at the best API testing tools for 2023.

What is API Testing?

API (Application Programming Interface) testing involves testing APIs directly to determine whether the developed API meets specific reliability, security, functionality, and performance requirements.

Regularly performing API tests can help software testers discover potential bugs, inconsistencies, or deviations and fix them before the user accesses the cloud service.

Unlike GUI tests, API tests focus primarily on the Business logic layer of software architecture instead of the application’s look and feel.

Furthermore, API and database testing are integral in the software development life cycle of APIs as they prevent lapses originating from APIs, which could affect end users.

Enlisting the Best API Testing Tools

Here listed are the most popular API testing tools for 2023:

SoapUI

SoapUI dedicatedly tests SOAP, REST, and GraphQL APIs. This complete API testing tool prioritises convenience for software developers and testers by offering a seamless graphical interface to execute automated functional, load, and regression tests.

Features

• It is an automated functional API testing tool requiring no code from testers.
• The tool supports simulations to help testers understand the behaviour of an application when accessible to end users.
• Its text generator can conduct various security scans on the applications to ensure it’s not vulnerable to attacks like cross-site scripting, XML bombs, SQL injections, etc.

Test Studio

Progress Telerik has developed Test Studio, which offers a simple-to-use testing solution. This API testing tool allows users to integrate RESTful APIs into any environment seamlessly.

Moreover, using Test Studio, software testers can automate API testing from end-to-end without a code while being rest assured that it will validate their models; integrity and reliability.

Features

• Test Studio allows testers to experience a fast-testing turnaround time while focusing on the right priorities.
• It offers dynamic API tests, enabling testers to set variables for chain requests, response values, and coverage for specific instances.

Katalon Studio

Katalon Studio is a free tool that is perfect for test data automation. You can use it to automate tests for applications, mobile apps, and web services. It is becoming popular as the go-to tool for testing API or Web services because of its comprehensive solutions for developers and testers.

Featuring all frameworks, plugins, and ALM integrations in a single package, Katalon Studio makes deployment much more seamless. Moreover, testers find its API testing platform relatively hassle-free.

Features

• It supports SOAP (simple object access protocol), REST (representational state transfer) requests, commands, and parameterised functions.
• Testers can do both automated and exploratory testing with this API testing tool.
• Katalon Studio allows testers to integrate UT and API/Web services across several platforms, such as Mac OS, Windows, and Linux.

Apigee

Offered by Google, Apigee is a cross-cloud API tool that can be used to develop and manage APIs. This tool allows users to access multiple features using other editors like Swagger and measure, build, test, and support APIs.

In addition, the added features like Open API 3.0 support, TLS (transport layer security), virtual host management improvements, etc., make API testing more flexible. Apigee supports creating and configuring API packages, reports, payment gateways, integrations, and revenue models.

Features

• Testers can identify performance problems by tracking API error rates, traffic, and response time.
• You can create and deploy API proxies in the cloud with the help of Open API Specification.
• Apigee offers a customisable developer portal as support for Node.js.

Postman

Postman is a Google Chrome plugin that has become one of the most widely used API testing tools. Its main objective is to test API services, but it has expanded its services to include native versions of Mac and Windows.

Either way, Postman is an excellent option for manual and exploratory testing. This tool allows you to monitor APIs, enable test data automation, debug, and run requests.

Features

• It allows writing the Boolean tests without requiring a command line.
• Postman’s interface can help you extract API data.
• The built-in tools of Postman give testers the ability to interact with an API.

Frequently Asked Questions (FAQs)

Is the demand for API testing increasing?

APIs are crucial to providing customers with a more connected and effective experience. Thus, businesses are starting to see the significance of API testing. Moreover, the IT sector’s growing complexity and advanced software development technologies are other demand-driving factors.

Does API testing require coding?

Automated testing is beneficial when testing APIs, specifically for DevOps, agile development, and continuous delivery. Testers can efficiently perform automated testing with API testing tools requiring no coding.

How can I choose the best API testing tool?

You should know that there is no ‘one-size-fits-all’ API testing tool. So, to choose the best API tool, you should evaluate testing options, consider each tool’s features, benefits, and drawbacks, and determine your needs.

Summing up it all

With software development technologies advancing faster and development teams becoming more technology-oriented, the value of API testing is increasing to provide improved applications to users.

More companies are now shifting towards automated Database Testing and API testing. Therefore, they look for the best test data management tools or testing tools to automate the API testing process seamlessly.

When searching for the right API testing tool, invest in one that can meet your organisation’s needs and boost revenue. Moreover, consider the features an API testing tool must have for smooth development workflows.