Minimize integration risks and maximize system reliability with our comprehensive software API testing services that drive business continuity.

Modern enterprises depend on APIs to connect applications, services, and data ecosystems. A single API failure can disrupt business operations, compromise user experiences, and impact revenue streams. Accelerate software reliability and performance testing with Kellton. We are the next-gen API Testing Company offering industry-aligned solutions that ensure seamless integration, robust security, and optimal functionality across all digital touchpoints.

Our enterprise-grade API Testing Services deliver comprehensive validation of functionality, performance, security, reliability, efficiency and usability to minimize operational risks and accelerate development cycles.

At Kellton, we transform API quality assurance through intelligent software testing methodologies, advanced automation frameworks, and proven industry expertise. Our dedicated API specialists ensure your digital infrastructure performs reliably under all conditions while maintaining the highest security and compliance standards.

25+

API Testing developers

150+

projects developed

15+

Years of Legacy

Our Enterprise API Testing Software Services Offerings

Our comprehensive API Testing Services portfolio covers every aspect of API validation, from functional accuracy to performance optimization and security assessment. As a reliable API Testing Company, we deliver tailored testing strategies that align with your business objectives and technical requirements.

Dedicated API Specialists

Our expert API testing professionals come with extensive API testing software experience across diverse testing methodologies, frameworks, and industry standards. Our specialists deliver tailored testing strategies aligned with your business objectives and technical requirements.

API Performance Testing

We offer comprehensive performance validation across multiple load scenarios to ensure optimal API responsiveness, throughput, and scalability. At Kellton, we identify API integration automation software performance bottlenecks and provide actionable optimization recommendations for enhanced system efficiency.

Automated API Testing

Streamlined automated testing frameworks that execute comprehensive test suites, including functional, regression, load, and security validation. Our automation approach reduces manual effort while ensuring consistent testing across development cycles.

API Functional Testing

End-to-end functional validation ensuring APIs perform according to specifications and business requirements. We verify request-response accuracy, data integrity, and compliance with defined API contracts and documentation.

API Reliability Testing

Systematic reliability assessment validating consistent API performance without interruptions, errors, or unexpected behavior. Our testing ensures dependable API operations across diverse usage scenarios and environmental conditions.

API Load Testing

Rigorous load testing simulating real-world traffic patterns to validate system performance under varying user volumes and transaction loads. We determine optimal capacity thresholds and scaling requirements.

API Security Testing

Comprehensive security validation including vulnerability assessment, authentication testing, authorization verification, and data protection analysis. We ensure APIs meet industry security standards and regulatory compliance requirements.

API Unit Testing

Granular unit-level testing of individual API components, functions, and methods to ensure accurate functionality and proper input-output handling. We validate the smallest testable API elements for reliability.

API Integration Testing

Comprehensive integration testing validating seamless communication between multiple APIs, third-party services, and system components. We ensure accurate data exchange, synchronization, and interoperability across integrated systems.

Why Choose Kellton for Next-Level API Testing Services?
As a trusted global partner for a functional software API testing company, Kellton offers seamless support for AI-driven secured posture across all types of APIs, UIs, and mobile-related security threats by running rigorous API tests faster. At Kellton, our tests are compatible with API architectural styles like REST, SOAP, and GraphQL APIs, along with schema validation, to ensure maximum compliance with API test requests.
At every touchpoint, our team of API testers ensures great user experiences across the API lifecycle. We use automated testing outputs and continuous performance monitoring of APIs to deliver superior quality assurance, combined perfectly with excellence, speed, security, reliability, and availability.

Extensive API Testing Experience:

With over 15 years of expertise, we deliver enterprise-grade API testing solutions tailored to diverse industries, ensuring high-performing, secure APIs for critical business applications.

Holistic API Validation

Comprehensive testing across functional correctness, performance tuning, security validation, and seamless integration, leveraging top-tier tools and proven methodologies.

Domain-Tailored Expertise

Specialized knowledge in financial services, healthcare, e-commerce, and technology, with a focus on compliance-driven API testing to meet stringent industry standards.

Flexible Service Models

Scalable engagement options, including dedicated API testing teams, project-specific services, or staff augmentation, customized to align with your timeline, budget, and resource needs.

Innovative Testing Solutions

Continuous adoption of cutting-edge testing tools, AI-driven analytics, and industry best practices to provide API testing services that enhance reliability and drive business success.

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Frequently Asked Questions (FAQ)

What is an API, and why is API testing important?

An Application Programming Interface (API) enables different software applications to communicate and exchange data. API testing is crucial because it validates functionality, performance, and security at the integration layer, identifying issues early in development before they impact user experiences or business operations.

Which is better for API testing: manual or automated testing?

Automated API testing is generally more efficient for regression testing, performance validation, and continuous integration scenarios. Manual testing remains valuable for exploratory testing, usability assessment, and complex business logic validation. The optimal approach combines both methodologies based on specific project requirements. .

What tools are commonly used for API testing?

Industry-standard API testing tools include Postman, REST Assured, SoapUI, JMeter, Katalon Studio, and Ready API. We select appropriate tools based on your technology stack, testing requirements, and integration needs to ensure optimal testing effectiveness and efficiency.

How much does API testing cost, and what factors affect pricing?

API testing costs vary based on project complexity, testing scope, automation requirements, and engagement duration. Key factors include number of APIs, testing types required, performance benchmarks, security assessment depth, and ongoing maintenance needs. Contact us for customized pricing based on your specific requirements.

Can API testing be integrated into a CI/CD pipeline?

Yes, API testing integrates seamlessly into CI/CD pipelines through automated test suites that execute during build processes. This enables continuous validation of API functionality, performance, and security throughout development cycles, ensuring rapid feedback and maintaining quality standards in agile environments.

What are the common challenges in API testing and how are they solved?

Common challenges include data dependency management, authentication complexities, version compatibility, and performance validation under varying loads. We address these through comprehensive test data management, robust authentication frameworks, version control strategies, and scalable performance testing methodologies.

How do you ensure API security during testing?

API security testing includes vulnerability assessments, authentication validation, authorization testing, data encryption verification, and compliance checking. We implement comprehensive security testing protocols including penetration testing, OWASP guidelines adherence, and regulatory compliance validation to ensure robust API security.