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:
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:
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.
Katalon is an all-in-one automated API testing tool. With Katalon you can:
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.
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
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: Postman alternatives for API testing
Website: Postman
Pricing: Free – $12/user/month
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.
Bruno is great for:
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
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.
Source: Google Cloud
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
In 2025, Apigee's latest version brings:
Website: Cloud Apigee
Pricing: Contact Sales
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
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:
| Tool | Best For | UI/CLI | Use Case |
|---|---|---|---|
| HTTPie | Developer-centric CLI workflows | CLI | Readable, scriptable API interactions |
| Postman | Manual and team-based API testing | GUI | Exploratory testing, team collaboration |
| cURL | Raw power and protocol options | CLI | System-level HTTP requests, scripting |
Assertible is an automated API testing tool that focuses on automation and reliability.
Feature highlights:
In October 2019, Assertible added the Encrypted variables feature, which provides a new way to store passwords, tokens, and secret data fields.
Website: Assertible
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:
For the Pro package, users can:
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
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:
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
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:
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
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:
Website: Pyresttest
Pricing: Free
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
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
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 and message-driven systems
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
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:
Website: Airborne
Pricing: Free
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.