Top Automated API Testing Tools For 2025

The number of API testing tools on the market for you and your team to try out and select will probably take forever. Here are several key considerations for you to keep in mind when choosing one:

• Basic API Requirements: Does it support the majority of the HTTP requests? Can settings and artifacts be imported from one project/test to another to save time?
• Complexity: Make sure the skillsets in your team are able to learn and use the software in the shortest time possible.
• CI/CD Integration: Check its list of integrations to see if the tool works with CI systems your team is using, like Jenkins or Bitbucket, and also if it’s native to avoid extra time trying to configure everything.   
• Interoperability: Can the tool be connected to communication platforms like Slack, project management systems like Jira, and Git for version control or your team’s toolchain?
• Non-technical Friendly: Read the tools’ documentation to see if they support BDD conventions and are able to export easy-to-understand reports.   

Top 15 API testing tools on the market

According to the State of Quality Report 2024, currently Katalon Studio, Postman, and JMeter the top API testing tools in their respective area of focus, with:

• Katalon Studio loved by 37% for its versatility in testing any AUT.
• Postman favored by 45% of users as great for API tests.
• JMeter by 31% for supporting performance testing.

You can have a look at the table below for a brief comparison of them, along with REST-assured and Apigee, which are great options also.

1. Katalon (Best for UI + API automation testing)

Katalon is an all-in-one automated API testing tool. With Katalon you can:

• Access pre-built API testing frameworks to start automating API tests without having to code. You only have to fill in the parameter details and Katalon takes care of the rest.
  
  
• Import existing Web Service requests from OpenAPI, Postman, SoapUI, WADLs. Katalon supports all types of SOAP/1.1, SOAP/1.2, REST, and GraphQL requests.
• Plug variables from a dataset to run API tests at scale, thanks to Katalon's pre-built data-driven testing framework
• Run UI tests for web, mobile, and desktop apps along with API tests to achieve the most comprehensive test coverage
• Schedule test runs, manage their status, categorize into test suites. A lot of API test management can be done within Katalon Studio.
• Integrate your automated API tests with top CI/CD tools to run them on predefined conditions
• Execute API tests in parallel from CLI to speed up API testing progress

After test runs, Katalon generates detailed reports with relevant metrics for you to monitor your efficiency and make data-driven decision.

📝 Want a customized automated API testing tool for your org? Share what you need and Katalon can help you build a tailored solution.

2. Postman (Best for API automation and exploratory testing)

Postman began as a simple Chrome browser extension. Since, it has evolved into a powerful, standalone cross-platform API development and testing solution available for Windows, macOS, and Linux. Postman supports a complete API lifecycle from design to testing, documentation, and monitoring.

Feature highlights:

• User-friendly REST client with an intuitive, modern interface

• Suitable for both automated and exploratory API testing

• Cross-platform availability: Mac, Windows, and Linux

• Built-in support for Swagger/OpenAPI, RAML, and other API schema formats

• Allows users to run, test, document, and monitor APIs in a unified workspace

• Rich collaboration features where users can share collections, tests, and mock data across teams effortlessly

• Robust integration ecosystem (GitHub, Jenkins, CI/CD pipelines, etc.)

Drawbacks:

• Can be heavy on memory for large projects or when handling big payloads

• Advanced features like API governance and analytics are locked behind paid tiers

• Not ideal for deep backend test scripting compared to code-based frameworks like REST-assured

• Limited CLI support without using Newman or Postman API

• Occasional UI lag on lower-spec machines

📚 Read More: Top 15 Postman Alternatives For API Testing

Website: https://www.getpostman.com/

Pricing: Free – $12/user/month

3. Bruno (Best for developers who want full control)

Bruno is a blazing-fast, offline-first, and fully open-source API client designed to rethink how developers manage and test APIs. It is even challenging traditional cloud-based tools like Postman and Insomnia.

Instead of relying on cloud sync or proprietary formats, Bruno introduces a developer-centric approach: API collections are saved directly to your local filesystem in a human-readable, version-controllable format using .bru files, which is its own plain-text markup language.

Who should use Bruno?

• Developers who love plain text API testing

• Teams working in secure environments with no internet access

• GitOps-minded devs who want full traceability of their API changes

• Tinkerers and open-source advocates looking for scriptable API tooling

Pricing: Completely free and open-source under the MIT License

Website: Bruno

GitHub: Bruno GitHub

4. Apigee (Best for Enterprise-grade API Management)

Apigee is a robust, cross-cloud API management and automated testing platform designed to help organizations build, secure, monitor, and scale APIs across hybrid and multi-cloud environments. It supports stringent compliance standards including PCI DSS, HIPAA, SOC2, and PII, making it suitable for regulated industries.

Apigee continues to be recognized as a leader in full lifecycle API management, most recently evolving to integrate AI-powered developer tools and zero-trust security frameworks.

Feature highlights:

• Full lifecycle support to design, implement, monitor, and extend APIs

• Multi-step testing and traffic orchestration powered by JavaScript

• Real-time diagnostics of API traffic, error rates, and latency tracking

• Simple deployment of API proxies using OpenAPI 3.0 specifications

• Integrated AI code suggestions, automated policy generation, and intelligent proxy design via Gemini AI

• Debug session REST API and modern horizontal sequence view (v2) for clearer API flow visualization

• Data Residency Zones and FIPS-compliant encryption for enhanced governance and compliance

• API Hub now enabled by default for new orgs to simplify discovery, reuse, and cataloging of APIs

Apigee is purpose-built for modern digital enterprises and data-driven, mobile-first apps. Since its major update in version 4.19.01, the platform has expanded significantly. New features like self-healing via apigee-monit, TLS enhancements, and virtual host management improvements are introduced.

In 2025, Apigee's latest version brings:

• Native support for Python 3
• Broader OS compatibility (RHEL 9, Rocky Linux 9, etc.)
• Improved security with BCFIPS
• More powerful observability tools.

Website: Cloud Apigee

Pricing: Contact Sales

5. JMeter (Best for performance and load testing of APIs)

Originally designed for performance and load testing, Apache JMeter has evolved into a versatile tool widely used for functional API testing as well. It supports testing for a variety of protocols, including HTTP, REST, SOAP, FTP, and more.

Feature highlights:

• Caching and offline replay of test results for streamlined debugging and re-analysis

• Built-in CSV data support to generate dynamic test parameters and simulate real-user traffic efficiently

• Seamless integration with CI/CD pipelines via tools like Jenkins, enabling automated test execution during deployment cycles

• Supports performance testing of both static and dynamic resources (e.g., HTML pages, APIs, JavaScript, etc.)

• Extended scripting capabilities with updated Groovy and BeanShell libraries for custom test logic

• Rich plugin ecosystem for flexible extensions, including reporting, assertions, and graphs

Drawbacks:

• Steep learning curve for beginners, especially when building complex test plans or using advanced scripting

• UI is outdated and lacks modern usability enhancements compared to newer tools like Postman or K6

• High memory usage during large-scale or distributed tests can strain system resources

• Limited native support for assertions and reporting without installing additional plugins

Website: JMeter Apache

Pricing: Free

Read More: Top Performance Testing Tools For Your Team

6. HTTPie

HTTPie is a modern, open-source command-line HTTP client built to make interacting with web APIs intuitive, readable, and developer-friendly. Positioned as a sleek alternative to tools like cURL and Postman, HTTPie simplifies everything from API testing and debugging to web scraping and automation scripting all from your terminal.

Feature highlights:

• Clean, colorized terminal output

• Intuitive syntax

• Built-in JSON support with automatic parsing and formatting

• Custom headers, data, query strings, and authentication with minimal boilerplate

• Forms and file uploads via multipart/form-data

• Persistent sessions using cookie storage across requests

• Wget-like downloads with support for saving responses to disk

• Works seamlessly on Linux, macOS, Windows, and FreeBSD

• Easily scriptable in CI workflows or shell scripts

Here's a quick HTTPie vs Postman vs cURL comparison:

7. Assertible (Best for Automated API monitoring & health checks)

Assertible is an automated API testing tool that focuses on automation and reliability.

Feature highlights:

• Support automating API tests throughout CI/CD pipeline
• Assist in running API tests after deployments and integrates with familiar tools (e.g., GitHub, Slack, and Zapier)
• Support validating HTTP responses with turn-key assertions
• Help testers update their tests when their specifications change by The Sync feature. Hence it’s needless to manually update tests after adding new parameters or changing the response of the API

In October 2019, Assertible added the Encrypted variables feature, which provides a new way to store passwords, tokens, and secret data fields. This offering is to improve API testing security practices. 

Website: Assertible

Pricing: Free – $25/month

8. Soap UI (Best for Enterprise-grade SOAP and REST testing)

SoapUI is a headless functional testing tool is dedicated to automate API testing. It allows users to test REST and SOAP APIs and Web Services with no hassles.

For the Free package, users can:

• Acquire the full source code and build their preferred features at hand
• Create tests effortlessly with Drag and drop, Point-and-click
• Reuse load tests and security scans for functional test cases in just several steps with Reusability of Scripts feature

For the Pro package, users can:

• Powerful data-driven testing – which means users can simulate how consumers interact with the APIs thanks to data loaded from files, databases, and Excel 
• Support native CI/CD integrations and asynchronous testing

The latest version SoapUI 5.7.0 includes support for GraphQL APIs and offers other improvements that make API testing more convenient and powerful. SoapUI now disables the Load and Save project scripts by default to enhance testing security.

Website: SoapUI

Pricing: Free – $749/year

9. Karate DSL (Best for Cucumber-style BDD API testing with minimal code)

This new open-sourced API testing tool assists users in creating scenarios for API-based BDD tests simply without writing definition steps. Indeed, KarateDSL creates those definitions itself, thus users can quickly kickstart the API testing. 

Feature highlights:

• Build on top of Cucumber-JVM
• Run a test and generate reports likewise to any standard Java project
• Supports configuration switching/staging, multithreaded parallel execution 

The latest revision, Karate UI 1.3.0, allows for Java 8 and introduces a slew of new features, including redesigned HTML reports, call-Single-Cache, Karate Robot Windows for Windows Desktop app automation, and enhanced tree walking in UI Tests. Also, Karate UI allows you to write tests in any language that can handle HTTP, JSON, or XML.

Website: Karate

Pricing: Free

10. Rest Console (Best lightweight manual API testing in the browser)

This tool is a REST/HTTP client for Google Chrome that allows users to visualize, construct, and send custom HTTP requests for testing and interacting with any RESTful API service. Rest Console offers an intuitive interface for composing requests, inspecting responses, and managing headers, bodies, and authentication with ease.

Feature highlights:

• Construct POST or PUT body via raw input
• Support to modify custom headers through intuitive UI
• Assist users in creating query parameters with ease
• Able to be used for several authentications like Plain, Basic, OAuth 
• Supports customizable interface

The most recent release, Rest Console v4.0.2, has been upgraded with several features to enhance user experience and bug fixes (e.g., oAuth improvements, Collapsible sections, Clickable Links in Response, UI enhancements).  

Website: RestConsole GitHub

Pricing: Free

11. Pyresttest (Simple YAML-based API test automation in Python)

It is a Python-based REST API testing platform that supports tests in JSON or YAML config files, no coding knowledge is required.

Feature highlights:

• Generate and validate mechanisms to build complete test scenarios
• Allow easy deployment on-server for smoke tests/health checks with minimal dependencies (pycurl, pyyaml, optionally future)
• Returns exit codes on failure to slot into automated configuration orchestration tools 

In 2016, the latest 1.7.1 version was released with a fixed JSONschema extension in Python 3 and added test coverage. This tool is best used for RESTful APIs.

Website: Pyresttest

Pricing: Free

12. Hoppscotch (Modern, fast, open-source API testing in the browser)

Hoppscotch is a free, open-source API request builder known for its speed, simplicity, and minimalistic UI. Originally created as a lightweight alternative to Postman, Hoppscotch allows developers to send HTTP requests, view real-time responses, and copy results, all within a clean, browser-based interface.

Feature highlights:

• Minimal, intuitive UI that loads instantly in the browser

• Real-time request/response panel for instant feedback

• Supports REST, GraphQL, WebSocket, SSE, and gRPC (experimental)

• Offers environment variables, pre-request scripts, and collections

• Allows export and import of requests for collaboration or version control

• One-click request copying, and ability to generate code snippets

• Easily self-hostable and customizable to fit internal use cases

• Built entirely using modern web technologies (Vue.js, PWA-ready)

Website: Hoppscotch

Pricing: Free

13. Taurus (Performance testing automation wrapper for JMeter, Gatling, Locust, etc.)

Taurus is a free and open-source test automation framework designed to simplify performance and API testing by abstracting away the complexity of traditional tools like JMeter, Gatling, and Locust.

With Taurus, you don’t need to write code or learn specific tool syntax. Instead, you define tests using a clean, human-readable YAML format.

Taurus is especially popular for teams who want to automate performance testing within CI/CD pipelines without investing in heavy scripting or GUI-based tools.

Feature highlights:

• Write test plans in YAML. This makes it accessible to testers without programming backgrounds

• Supports JMeter, Gatling, Locust, The Grinder, and Selenium, allowing you to run those tools using a unified interface

• CI/CD integration friendly

• Live console and graphical reports

• Supports functional and performance testing of APIs, web UIs, and services

• Excellent for load testing APIs and automating benchmark validations with minimal setup

Website: Taurus

Pricing: Free

14. Citrus Framework (Complex end-to-end integration testing)

Citrus is a powerful, open-source integration testing framework for messaging-based systems. Built for Java developers, it provides a fluent Java API to define test logic and automate message-based interactions, whether HTTP, REST, SOAP, JMS, Kafka, MQTT, or custom protocols.

Feature highlights:

• Fully automated tests using a Java fluent DSL for defining complex messaging flows

• Acts as both a consumer and producer, enabling end-to-end simulation of API exchanges

• Supports a wide range of protocols and transports, including HTTP, SOAP, REST, JMS, Kafka, MQTT, TCP/UDP, and more

• Built-in support for schema validation, XPath/JSONPath assertions, and custom test scripts

• Compatible with JUnit, TestNG, and Maven/Gradle build systems

✅ Best for:

• Java teams testing microservices, message-driven systems, or B2B integrations

• Projects requiring simulation of external systems or orchestration of multi-step API flows

• Developers needing fine-grained control over messaging and validation logic in automated tests

Website: Citrus Framework

Pricing: Open-source

15. Airborne (RSpec-style API testing in Ruby)

Airborne is a lightweight, Ruby-based API automation testing framework built on top of RSpec. Designed for developers and testers who prefer a code-first approach, Airborne enables fast, expressive HTTP tests without the overhead of a graphical user interface.

Feature highlights:

• Clean, declarative syntax for API assertions using RSpec-style matchers

• Designed specifically for REST API testing

• No GUI. Tests are written directly in Ruby scripts

• Supports JSON response validation, status code checks, and header inspections

• Easily integrated into CI/CD pipelines for test automation

  Fully open-source and free to use

Website: Airborne

Pricing: Free

Conclusion

Although we have introduced some of the best testing tools on the market, it is essential to keep the pros and cons in mind. You may need to be flexible in trying various options before finding the one that best suits your requirements.