Buyer's guide

Best API Testing Tools software

Platforms for testing API functionality, performance, and security. Open any profile for real pricing, compliance, and buyer-fit detail, or jump into the api testing tools directory to filter by industry, company size, and certifications.

17 profiled toolsUpdated 2026

1
Browserbase
AI Agents & Sidekicks
Browserbase provides a reliable, managed browser infrastructure for AI agents, enabling web scraping, automated testing, and agent-based web interactions at scale.
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2
Scalar
Developer Experience Platforms
Scalar provides a modern toolkit for API documentation, request testing, and developer-facing API experiences built around OpenAPI.
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3
Postman
API Testing Platforms
Postman is an API platform for designing, testing, documenting, and monitoring APIs with collaboration features for developer teams.
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4
Pact
Contract Testing
Open source contract testing framework ensuring microservices communicate correctly by verifying API interactions between consumers and providers.
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5
Playwright
End-to-End Testing
Playwright is an open-source end-to-end testing framework by Microsoft for testing web applications across Chromium, Firefox, and WebKit with a single API.
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6
CircleCI
CI/CD
CircleCI is a continuous integration and delivery platform that automates build, test, and deployment pipelines. It supports cloud and self-hosted environments with powerful parallelism and…
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7
Hoppscotch
API Testing Tools
Hoppscotch is an open-source API development platform providing a fast, lightweight alternative to Postman for testing REST, GraphQL, WebSocket, and MQTT APIs.
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8
Mailjet
Email Deliverability
Mailjet by Sinch is an email delivery and marketing platform with collaborative editing, API sending, and real-time analytics for teams.
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9
Checkly
Monitoring & Observability
Checkly is a monitoring-as-code platform for API monitoring and end-to-end testing that integrates with CI/CD pipelines to detect issues before they affect users.
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10
MSW
API Mocking
API mocking library for JavaScript that intercepts network requests using Service Workers for browser and Node.js testing.
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11
Hoverfly
API Mocking
Lightweight API simulation tool for creating HTTP service virtualizations to enable fast parallel development and testing.
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12
Swagger
API Testing Platforms
Swagger by SmartBear provides API design, documentation, testing, and governance tools built around the OpenAPI specification standard for API-first development.
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13
Artillery
Load Testing
Modern load testing and smoke testing tool for APIs and web apps with a focus on developer experience and CI/CD integration.
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14
Mailgun
Email Deliverability
Mailgun by Sinch is a transactional email API service for developers, providing email sending, receiving, validation, and deliverability optimization.
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15
WireMock
API Mocking
Flexible API mocking tool for testing microservices and APIs by simulating HTTP-based APIs for reliable integration testing.
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16
Checkmarx
DevSecOps Platforms
Checkmarx provides a comprehensive application security platform including software composition analysis, SAST, DAST, and API security for enterprise DevSecOps programs.
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17
StatusCake
Website Uptime Monitoring
StatusCake provides uptime monitoring, page speed testing, SSL monitoring, and hosted status pages for websites and APIs.
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18
HTTP Toolkit
API Testing Tools
Open source tool for debugging, testing, and building with HTTP and HTTPS traffic interception.
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19
httpie
API Testing Tools
Human-friendly command-line HTTP client for API testing providing intuitive syntax and JSON support.
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20
Karate Labs
Test Automation Frameworks
Open source API testing framework combining test automation with API mocks and performance.
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21
mitmproxy
API Testing Tools
Open source interactive HTTPS proxy for intercepting, inspecting, modifying, and replaying web traffic for debugging.
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22
Stubbornjava
API Testing Tools
Lightweight framework for building mock HTTP servers in Java for integration testing of APIs.
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23
Mockoon
API Mocking
Desktop application for creating mock REST APIs with templating, response rules, and proxy mode for local development.
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24
Hurl
API Testing Tools
Command-line tool for running HTTP requests defined in plain text with assertions for testing APIs.
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25
Mockbin
API Mocking
Simple mock HTTP server by Kong for testing and debugging HTTP calls from your apps.
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26
Microcks
API Mocking
Open source Kubernetes-native tool for mocking and testing APIs and microservices from OpenAPI and AsyncAPI specs.
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27
Apifox
API Design Tools
Chinese-founded API design, debugging, and testing platform used globally.
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28
REST-assured
API Testing Tools
Java library for testing and validating REST services with a domain-specific language for writing readable API tests.
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29
Bruno
API Developer Tools
Open source API client that stores collections directly in your filesystem using a plain text markup language.
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30
Charles Proxy
API Testing Tools
HTTP proxy and monitor tool enabling developers to view HTTP and SSL traffic between their machine and the internet.
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31
Beeceptor
API Testing Tools
Mock HTTP server and request inspector providing instant endpoints for testing and prototyping APIs.
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32
SoapUI
API Testing Tools
Open source API testing tool by SmartBear supporting REST, SOAP, and GraphQL with assertion-based validation.
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33
Loadster
Software
Distributed load testing for websites and APIs.
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34
Fiddler
Developer Tools
Web debugging proxy from Progress logging HTTP/HTTPS traffic for debugging web application issues and testing APIs.
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35
Wiretap
API Testing Tools
Open-source OpenAPI-aware HTTP proxy for validating API requests and responses against schemas in real time.
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36
Kreya
API Developer Tools
GUI client for gRPC, REST, and WebSocket APIs with scripting support and environment management.
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Best api testing tools by company size

Best api testing tools for Solo / freelancer Best api testing tools for Startup (1-50)Best api testing tools for Small business (51-200)Best api testing tools for Mid-market (201-1,000)Best api testing tools for Enterprise (1,000+)

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Frequently asked

What is the best api testing tools software?

Cubbie ranks 17 profiled api testing tools tools by profile completeness, verified-vendor status, and active deals. The list above leads with the products that carry the most complete, vendor-maintained profiles.

How does Cubbie choose these api testing tools tools?

Listings are drawn from the live catalog and ordered so products with substantive, vendor-maintained profiles surface first. Cubbie does not accept payment for ranking position.

Ranked from Cubbie's live catalog, https://www.cubbie.com/best/api-testing-tools