best api testing tools

API Testing Tools, Approaches & Frameworks for 2022

Table of Contents

Reading Time: 8 minutes

APIs are now required for every mobile app development company for application development. This means that APIs must be thoroughly tested before being released to clients or end users. So, what is API testing? It ensures that the functional goals of an API endpoint can be met while being subjected to actual load conditions. Thousands of open APIs must be improved in terms of security, dependability, and performance to make the app robust and tamper-proof. The API layer contains an application’s business logic, which governs how users interact with the app’s services, data, and features. This is why using API tools and frameworks in the right approach is essential.

Here are some interesting stats about APIs and their demands,

  • According to MarketsandMarkets, the API management market will be worth $5.1 billion by 2023, growing at a CAGR of 32.9%.
  • The API management market is expected to reach USD 13.7 billion by 2027, up from USD 4.5 billion in 2022, at a CAGR of 25.1%. As the API economy grows, data and services become more accessible.
  • ProgrammableWeb has over 24,000 APIs available.
  • There are about 2 million API repositories on GitHub.
  • OpenAPI is used by more than 93% of communication service providers.
  • By 2024, there will be 130 million Open Banking users.
  • API-based services account for 83% of all Internet traffic.

Now you know how important it is to consider API development and select relevant API testing tools for the same. Let’s dive deep to know why we need APIs, what are the top API tools and frameworks, and what is the best approach to follow.

Why Use API Tools?

Since software evolves so quickly, having tests that provide feedback to app developers and testers as soon as possible is critical. The primary advantage of API testing tools is the ability to access applications without using a user interface.

Using API testing automation tools, you can detect changes in request-response format or API changes early in the testing phase. Simplifying the integration and regression testing phases contributes to a shorter software testing life cycle. Testing the application’s core, code-level functionality prior to performing GUI tests allows for an early assessment of the build’s overall strength.

Overall, your project will be a huge success if API testing tools are taken advantage of!

Best API Testing Tools to Use in 2022

The top API testing tools are listed below!

1. SoapUI

The open-source, cross-platform SoapUI API testing tool allows testers to run automated regression, functionality, load, security, and compliance tests. The QA team can test all APIs since SoapUI supports many industry-standard protocols such as SOAP/WSDL, JMS, REST, AMF, and JDBC.

It has a simple user interface with drag-and-drop functionality that even non-technical users can quickly grasp. It also allows testers to create data-driven test scenarios and makes debugging easier. For more complex scenarios, testers can create their scripts. SoapUI is compatible with a wide range of popular API testing automation tools, including Maven, Junit, Hudson, and others.


  • SoapUI Pro, the commercial version, includes productivity tools.
  • Swing, which is entirely Java-based, is used to create the user interface.
  • It helps perform simulation, invocation, inspection, functionality, and security testing effortlessly.
  • Excellent tool for testing vulnerabilities and providing options for tamper-proofing websites against hackers.
  • Existing test suites can be copied and reused in other projects with the cloning feature.

2. Testim

Testim, a comprehensive test automation platform, includes API testing as a subset. Testim’s use of Artificial Intelligence to help with test suite creation, execution, and maintenance is intriguing. 


  • Without a doubt, the framework that learns with each test suite execution and maintenance task is the most notable feature here.
  • For common testing tasks, testers can create API actions and validations.
  • Allows isolating UI testing by efficiently using the user interface while removing data from the API.
  • It’s a better way to test both the UI and the API at the same time.

3. Postman

To create and test APIs, Postman, an open-source, simple-to-install tool, can be used. Postman is a capable alternative for exploratory-style API testing if more integrated solutions are required.


  • For each request, JavaScript is used to create and run tests.
  • When using Postman to test APIs, the developer can use HTTP methods such as GET, PUT, and POST.
  • Endpoints that are related to one another should be collected.
  • It is one of the most widely used API testing tools. REST-Assured is the best Java API automation option. Rest Assured is a Java library that allows you to test and validate REST APIs.

4. Smartbear

Smartbear’s TestComplete feature automates user interface testing for a variety of desktop applications written in Windows, WPF, Java, .Net, or other programming languages. It improves your ability to run automated tests using test scripts and includes record and replay functionality, enabling QA teams to perform continuous testing.


  • Cross Browser Testing by Smartbear simplifies cross-browser compatibility testing.
  • Its ReadyAPI solution allows test engineers to improve API quality faster by leveraging web services like GraphQL, RESTful, and SOAP.
  • Smartbear acquired open-source Cucumber to broaden its robust test product line by combining test automation expertise with Cucumber’s leadership in a behavior-driven development (BDD).

5. JMeter

JMeter is used in a variety of testing scenarios, including load testing, functional testing, and unit testing. It is primarily intended for use with web applications, but it can also be used for basic performance monitoring. JMeter works with a variety of servers and protocols, including HTTP, HTTPS, SOAP, LDAP, and FTP. It is completely open-source and free to use.


  • It has a multithreading framework that allows multiple thread groups to sample at the same time, is very extensible, and stores test plans in platform-independent XML files.
  • For various programming languages, including PHP and Java, there are numerous extensions and plugins available.

6. RapidAPI

RapidAPI is used for a variety of purposes, including testing, design, and monitoring. It supports all API types and has a user-friendly interface. App developers and testers can easily create detailed functional tests for more thorough API validation. It can be used in conjunction with a continuous integration/continuous delivery pipeline and offers centralized monitoring. It is also capable of testing all SOAP, GraphQL, and REST APIs.


  • Developers can manage all API interactions in a single location.
  • Allies to try out the tool by creating a free account.
  • It is a comprehensive cloud API testing tool.
  • Users can view all of the APIs associated with their accounts via the testing dashboard.

Top 5 Approaches

When testing data-driven APIs, follow these five simple best practices to ensure worthwhile results!

Use Clear-sighted Data

The testers must begin with the business processes that your API was designed to support to ensure that your test data is realistic. They must distinguish between business users and API testers, and prioritize theoretical and practical knowledge of the API’s purpose and data. Then, it is essential to consider the possibility of a large number of ambiguous data relationships. They should be able to accurately represent these relationships in their test data with the right tools.

Test Both Best-case & Worst-case Scenarios

The vast majority of people believe that only positive API responses should be tracked. The API invoker should be notified if a server-side operation receives valid data. It’s also critical to ensure that passing incorrect or otherwise invalid parameters to the API results in a negative result, which is typically an error message or another indication of an issue. The tester is not required to sift through the entire set of results in order to identify a point of failure with this approach to API evaluation. It is important to investigate both constructive and destructive use cases.

Drive Assertions Through Data

Assertions are rules that specify how an API request should be handled. They are the primary quality metrics because they are used to determine whether or not the API is behaving normally. Many app testers make the mistake of hard-coding these guidelines, which increases maintenance costs and brittleness in the API evaluation process. In contrast, dynamic assertions are adaptable and can change from one API request to the next. So, it is important to align them with relevant data and validate the same.

Follow API responses

Many testers become fixated on the success or failure of each API invocation after completing their functional tests and ignore the set of responses. Unfortunately, API responses are extremely valuable artifacts. If these test results are not recorded, important history is lost. When an API is changed several times and a new error is discovered during the regression testing process, determining which change caused the bug can be difficult. Using a library of previously saved API requests and responses makes it much easier to locate and resolve the exact point at which the new issue first appeared.

Take Care of API Performance & Security

Many businesses rely on irrational, narrowly focused performance and security tests constrained by small sets of hard-coded test data. Why not use the rightly configured, adaptable data-driven functional test for multiple purposes after putting in the time and effort to set it up? The reuse of a data-driven functional test adds much-needed realism to performance and security evaluation processes, and excellent API testing tools make the transition simpler than before.

Open Source API Frameworks Available

Here are some of the open-source API testing frameworks you should be aware of!

  1. Insomnia
  • Application for testing Rest API and GraphQL. 
  • Supports a number of community plugins, such as JWT support and Open API validation.
  1. Requester 
  • The requester is the HTTP client for Sublime 3’s popular text editor. 
  • It enables API testing to be performed directly in Sublime.
  1. Dredd 

Dredd is a command-line tool written in JavaScript and NodeJS that compares API specification documents to actual API implementations.

  1. Swagger Test Templates 

This framework, which is based on JavaScript and NodeJA, allows the creation of tests from Open API specifications.

  1. Hippie 

A JavaScript and NodeJS-based library for creating HTTP API tests that add a layer of functionality and assertions.

  1. Frisby 

Numerous API-specific assertions and validations are included in this framework for testing the JavaScript and NodeJA APIs. 

  1. Apickli
  • It is a rest API integration testing framework based on JavaScript and NodeJA, with BDD and Gherkin support. 
  • Several predefined API testing assertions are included.
  1. Chakram

A testing framework for JavaScript and NodeJS-based end-to-end APIs.

  1. Zerocode 
  • Zerocode is a Java-based interface testing framework. 
  • Depending on the configuration, it can test Rest, Soap, and any HTTP-based API.
  1. Karate
  • API performance testing, API mocking, and API test automation in Java.
  • It uses the Cucumber JVM.
  1. Pandaria

HTTP testing framework based on Java. The Cucumber JVM is used for the BDD portion.

  1. Gatling 
  • Gatling is a Scala-based strong HTTP testing framework. 
  • Its applications include simulating multiple client applications, complex Rest API test scenarios, and different API request flows.
  1. Pact 
  • Pact is a framework for API contract testing and validation. 
  • It ensures the validity and enforceability of the contract between the API service and the customer.

API Testing Workflow

  1. Create API Testing Specifications

Before planning API tests, the tester must first define the testing boundaries and requirements. The API’s goal and intended user, application workflow, API features and functions, and other topics will be covered here.

  1. Build a Test Environment for APIs

Following the determination of your API’s functional scope, the next step is to create an API test environment, which is typically handled by DevOps engineers.

  1. Send a Test API Call

Before beginning thorough testing, it is necessary to make an API call to ensure that the API is operational and that nothing is broken.

  1. Set the Input Criteria

Consider every possible input configuration. They will be used in the test cases, and the results will be authenticated to ensure that the API is working properly.

  1. Write & Run Test Cases for APIs

The testers must write and run test cases after completing all of the necessary preparations, then compare the results to what was expected. It’s a good idea to sort them into test category groups.

Concluding Words

Each of the aforementioned API testing tools is effective in its own way, making it impossible to choose one over the others. Finding a single tool that can do it all can be difficult, but it is critical to implement a toolset that meets your business’s needs while increasing revenue. As a result, choosing API testing tools, frameworks, and approaches after thoroughly testing a few of them and determining which one best meets your needs is critical in this situation.

Pyramidion’s testing software experts can create a customized shortlist of software options with objective recommendations to assist you in selecting the options that best meet the needs of your business. We house the best development, design, and QA team who hold expertise in advanced technologies. Connect with us to arrive at our API development and testing services!

Related Posts

Write A Comment