API Testing Services - DeviQA
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API Testing Services

Ensure that your API is defined and implemented correctly before you publish it


37 reviews

Software testing company with 5-star reviews on Clutch, GoodFirms, and G2.

Years on the market

14 +

Software QA engineers

250 +



Projects tested from scratch

300 +

Integrations into an existing development & testing process

200 +

Clients over the globe

300 +

Developing an API can empower a business with increased flexibility, collaboration opportunities, innovation, and the ability to adapt to changing market demands. It's a strategic investment that can contribute to the overall growth and competitiveness of a business in today's interconnected digitalized world. However, like any piece of software, an API requires rigorous testing to ensure it adheres to the given requirements. That's where our API Testing Services come in, ensuring all the aspects of your API meet the highest standards.

Our Solutions For Your API Testing Challenges

At DeviQA, we understand the intricacies of API testing and the challenges that come with it. Our expertise lets us address all these challenges efficiently, propelling your development and quality assurance processes forward. Here are some common API testing challenges and the ways we tackle them:

Dependency on External Services


Modern APIs may depend on external services that are not always available or reliable during testing. This poses a serious challenge.


We simplify test configuration through automation. Our experts provide user-friendly tools that enable you to effortlessly set up test environments. With our solutions, you can save time and eliminate errors associated with manual configurations.

Data Sensitivity


Testing APIs often involves sensitive data, making it challenging to create realistic test scenarios without exposing sensitive information.


Our QA experts leverage mock servers or stubs to simulate external services. In such a way testing is executed in controlled environments without relying on the availability of external dependencies.

Security Vulnerabilities


Identifying and addressing security vulnerabilities is critical but challenging.


We conduct thorough security testing, including penetration testing, and regularly update security measures collaborating with security experts to ensure a robust security posture.

The Scope of Our API Testing Services

Executing a wide range of tests both manual and automated, DeviQA’s experts check diverse aspects of API operations.

API Functional Testing

Ensure that your API functions as intended by thoroughly testing its individual components and functionalities. We validate inputs, outputs, and expected behaviors to detect any issues early in the development process.

API Performance Testing

Optimize the speed and efficiency of your API with performance testing. We evaluate response time, scalability, and resource usage to identify and address bottlenecks, ensuring your API can handle peak loads with ease.

API Security Testing

We perform the whole scope of security tests to identify possible vulnerabilities. We check for common security issues, such as SQL injection, cross-site scripting (XSS), and proper handling of sensitive information.

API Integration Testing

Verify the smooth integration of your API with other software components. We thoroughly examine how your API interacts with third-party services, ensuring that seamless data flows.

API Fuzz Testing

Identify potential vulnerabilities in your API by subjecting it to a wide range of unexpected inputs and data formats. This method helps uncover hidden issues that might not be apparent during regular testing.

Endpoint Verification

We rigorously test each API endpoint to ensure that it accepts requests, processes them correctly, and returns expected responses. Particular attention is paid to parameters, request methods, and response status codes.

Input and Output Validation

We send requests with valid and invalid to verify that the API handles input validation correctly. Similarly, we validate the output data to ensure it matches the expected format and values.

API Documentation Testing

We validate that the API documentation is accurate and up-to-date and ensure that it provides clear instructions on how to use the API, including endpoints, parameters, authentication methods, and example requests and responses.

Partner With Us: See the Difference

Test coverage :



2.5 weeks to run regression testing

1 day to run regression testing

7 days to run smoke testing

1 day to run smoke testing

Outdated test cases

60% increase in the number of regression tests and relevant test cases

50% test coverage

90% test coverage

Supported localizations were not tested

27 localizations supported by QA engineers

No automation testing

>1500 automated test scenarios created

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Dev capacity:



Didn’t have a formal QA process

Built smooth and well-working processes

Didn’t make automated testing

Test automation : smoke, API, UI on all supported browsers

Testing was carried out by the devs

Full coverage of the application by test cases

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Test coverage :



Existing workflow in Jira didn’t allow to understand how many bugs were left unfixed before the release and their priorities

Adjusted the Jira workflow, integrated TestRail with Jira to be able to see statisticls of the issues per release

The lack of test documentation

Developed necessary test artifacts that adhere to industry standards and are easily maintainable

No Automation test coverage

Added multithreading to run tests in parallel on 10 different threads, which reduced the time of the test run in 7 times

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