Best Free API Testing Tools of 2025

Compare the Top Free API Testing Tools as of July 2025

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What are Free API Testing Tools?

API testing software is used to test and validate the functionality, performance, security, and reliability of Application Programming Interfaces (APIs). These tools help ensure that APIs perform as expected under various conditions and meet the required business and technical requirements. Features typically include automated testing, request/response validation, load testing, security testing (e.g., for vulnerabilities and authentication), and performance testing. API testing software often supports integration with continuous integration/continuous deployment (CI/CD) pipelines to facilitate automated testing as part of the software development lifecycle. Compare and read user reviews of the best Free API Testing tools currently available using the table below. This list is updated regularly.

1

Boozang

Boozang

Build. Test. Automate. Empower your whole team to build and maintain automated tests, not just developers. Meet your testing demands fast. Get full test coverage in days, not months. Our natural-language tests are extremely stable to code changes. When tests break our AI will repair it in minutes. Go Agile/DevOps by setting up Continuous Testing. Push features in production the same day. Boozang supports the following test approaches: - Codeless Record/Replay interface - BDD / Cucumber - API testing - Model-based testing - HTML Canvas testing The following features makes your testing a breeze - In-browser console debugging - Screenshots to show where test fails - Integrate to any CI server - Test with unlimited parallel workers to speed up tests - Root-cause analysis reports - Trend reports to track failures and performance over time - Test management integration (Xray / Jira)

15 Ratings

Starting Price: $249 USD / month / user

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2

Testim

Tricentis

Testim is the fastest path to resilient end-to-end tests—codeless, coded or both. Testim lets you create amazingly stable codeless tests that leverage our AI, but also the flexibility to export tests as code. You can leverage Testim’s modern JavaScript API and your IDE to debug, customize or refactor tests. Store them in your version control system to keep them in sync with branches and run tests on every commit. Run parallel, cross-browser tests on our test cloud or Selenium-compatible grids while integrating with your CI and dev tools to run smoke tests on pull requests, end-to-end tests on release candidates, or full regression suites on a schedule. Customers like Microsoft, Salesforce, NetApp, Wix, and JFrog run millions of tests on Testim each month. Learn more on our website and sign up for your free account!

13 Ratings

Starting Price: $20,000 a year

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3

Cerberus Testing

Cerberus Testing

Cerberus Testing is a low-code software testing automation enabling continuous testing at scale. Using the solution you can remove years of implementing an internal testing framework. The product enables you to quickly iterate through your testing lifecycle, from test repository, execution, reporting and analytics. The solution allows the collaboration of the teams from the use-cases definition to the test case execution on the variety of browsers, devices, apps and APIs. You can leverage your own or external robots infrastructure to execute your test at scale, enabling you to focus on your business value. It supports various integrations for speed of implementation such as Jenkins, Bitbucket, Slack, Kafka. It is available and maintained in open-source by various digital and retail players such as La Redoute, Decathlon, Adeo, and Norauto.

10 Ratings

Starting Price: €0

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4

Fiddler

Progress Software

Capture all HTTP(S) traffic between your computer and the Internet with Telerik Fiddler HTTP(S) proxy. Inspect traffic, set breakpoints, and fiddle with requests & responses. Fiddler Everywhere is a web debugging proxy for macOS, Windows, and Linux. Capture, inspect, monitor all HTTP(S) traffic between your computer and the Internet, mock requests, and diagnose network issues. Fiddler Everywhere can be used for any browser, application, process. Debug traffic from macOS, Windows, or Linux systems and iOS or Android mobile devices. Ensure the proper cookies, headers, and cache directives are transferred between the client and server. Supports any framework, including .NET, Java, Ruby, etc. Mock or modify requests and responses on any website. It’s a quick and easy way to change the request and responses to test websites without changing code. Use Fiddler Everywhere to log all HTTP/S traffic between your computer and the Internet.

2 Ratings

Starting Price: $12 per user per month

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5

ZAPTEST

ZAPTEST Inc.

ZAPTEST is a leading Free and Enterprise software test automation and RPA tool. Offerings include Computer Vision technology that allows for Cross-Platform digital interface automation for UI, API, Load testing, and RPA in a seamless process. Combine that with our 1SCRIPT methodology, seamless automation, parallel execution, and unlimited licenses– you get an efficient testing suite that generates up to 10X ROI. We promise that if you can perform a procedure via any digital interface (live application or mockup) manually, ZAPTEST can automate this procedure As-Is! With ZAPTEST’s Enterprise Solution subscription program, you receive unlimited licenses across the entire organization. Regardless of whether your automation needs increase, your cost remains fixed. FARM allows ZAPTEST users to manage all of their devices so you can remotely control cross-environments and projects from any location. ZAPTEST uses many practical applications to enhance its software testing software capabilities

1 Rating

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6

Xano

Xano

Xano provides a fully-managed scaleable infrastructure to power your backend. On top of that security, you can quickly build the business logic that powers your backend without a single line of code or use one of our pre-made templates to launch quickly without sacrificing scale or security. Build custom API endpoints without a single line of code. Accelerate time to market using our out-of-the-box CRUD operations and Marketplace extensions and templates! Your API comes “ready-to-use” so you can immediately connect to any frontend and focus on your business logic. Everything is also automatically documented in Swagger so connecting to a frontend is a breeze. Xano uses PostgreSQL which provides the flexibility of a relational database along with the Big data needs of a NoSQL solution. Add features to your backend in a few clicks or start with ready-made templates and extensions to jumpstart your project.

1 Rating

Starting Price: $29 per month

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7

Ambassador

Ambassador Labs

Ambassador Edge Stack is a Kubernetes-native API Gateway that delivers the scalability, security, and simplicity for some of the world's largest Kubernetes installations. Edge Stack makes securing microservices easy with a comprehensive set of security functionality, including automatic TLS, authentication, rate limiting, WAF integration, and fine-grained access control. The API Gateway contains a modern Kubernetes ingress controller that supports a broad range of protocols including gRPC and gRPC-Web, supports TLS termination, and provides traffic management controls for resource availability. Why use Ambassador Edge Stack API Gateway? - Accelerate Scalability: Manage high traffic volumes and distribute incoming requests across multiple backend services, ensuring reliable application performance. - Enhanced Security: Protect your APIs from unauthorized access and malicious attacks with robust security features. - Improve Productivity & Developer Experience

1 Rating

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8

Alithya GoTest

Alithya

Alithya GoTest is a collaborative test hub that is easy and quick to master and integrate, ensuring the quality of any professional digital solutions for companies requiring reliability without compromises. Ensure the quality of your application without sacrificing speed or agility with an easy-to-use, GUI test automation tool. Whether using scripts or not, our flexibility is unmatched, letting you create manual, automated or hybrid test suites for every desktop, web, and mobile application with ease including .Net, Java, WPF and Windows 10, modern JavaScript frameworks like React and Angular and iOS or Andoid with 2050+ browser and platform configurations. No need to jailbreak your devices. Alithya GoTest comes with a keyword library of over 1500 keywords, so you can ensure your GUI and API tests are scalable, robust, and easy to maintain. Alithya also offers consulting, coaching and training to ensure the success of your teams.

1 Rating

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9

HttpMaster

Borvid

HttpMaster is a debugging and testing tool for various HTTP applications with special focus on web APIs and RESTful web services. Key features: - HttpMaster project to store complete definition of HTTP calls in one single place. - Broad set of HTTP properties (HTTP headers, URL encoding, etc.). - Dynamic parameters to simulate variations of input data or create global API values. - Response data validation with logical expressions. - Request chaining to use data from previous request with the next request. - Extensive data upload support, including 'multipart/form-data'. - Request data builder for creating request body with an optional dynamic parameters. - Request item execution with detailed progress monitoring. - Execution groups to create batches of requests. - Comprehensive execution data review and management. - Basic request tool for ad-hoc execution. - Command line interface. - PDF reports. - Support for cURL commands.

Starting Price: Starting from $69

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10

SyncTree

Ntuple

SyncTree strives to be a "Super Connecting Platform" that can easily connect any services you want. With SyncTree, which consists of SyncTree STUDIO, a solution for building backend business logic with block coding, and Block Store, a platform for buying and selling pre-made backend function blocks like App Store, you can organically utilize data and connect services to achieve unlimited service expansion. Based on aPaaS, Block Store provides APIs from various services such as ChatGPT, DALLE, YouTube, etc. in the form of 'backend function blocks', which you can subscribe to and then combine as you want quickly in SyncTree STUDIO to build your business logic. SyncTree is for everyone, whether you're an individual or a business, and you can subscribe and use it according to your needs, from the free version to the PRO version.

Starting Price: Free/1Month/3,000 Call

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11

Telepresence

Ambassador Labs

Telepresence streamlines your local development process, enabling immediate feedback. You can launch your local environment on your laptop, equipped with your preferred tools, while Telepresence seamlessly connects them to the microservices and test databases they rely on. It simplifies and expedites collaborative development, debugging, and testing within Kubernetes environments by establishing a seamless connection between your local machine and shared remote Kubernetes clusters. Why Telepresence: Faster feedback loops: Spend less time building, containerizing, and deploying code. Get immediate feedback on code changes by running your service in the cloud from your local machine. Shift testing left: Create a remote-to-local debugging experience. Catch bugs pre-production without the configuration headache of remote debugging. Deliver better, faster user experience: Get new features and applications into the hands of users faster and more frequently.

Starting Price: Free

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12

Treblle

Treblle

Treblle is a federated API Intelligence platform built for enterprises that need full visibility, control, and security over their APIs. With a single integration, Treblle provides real-time API Discovery, Observability, Analytics, Governance, Runtime Security, and Developer Portals. It supports on-prem and private cloud deployments to meet strict compliance and data privacy requirements. Treblle helps teams shift left by surfacing API issues early in development and ensuring consistency across environments. Its AI-powered Integration Assistant simplifies onboarding and reduces manual effort. Trusted by global enterprises and recognized over 15 times by Gartner, Treblle accelerates innovation while giving you complete control over your API landscape.

Starting Price: $25 per month

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13

Assertible

Assertible

The easiest way to test and monitor your web services. Gain confidence in critical infrastructure by using Assertible's automated QA tools to test and monitor your web services across deployments and environments. Assertible provides a reliable first line of defense against web service failures by providing simple and powerful assertions to test and monitor your APIs and websites. Lower the number of false positives in your automated QA tests and be confident your APIs are healthy. Keeping your tests up to date can be a burden, but with Assertible you can automatically sync your API tests with the latest changes in your specification. As you add and update responses, parameters, headers, and more, updating your Assertible API tests is as easy as clicking sync. Assertible integrates with the tools you're already using and lets you do things like execute your web app tests when you push code to GitHub, or send alerts to Slack if failures happen.

Starting Price: $25 per month

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14

BlazeMeter

BlazeMeter

BlazeMeter’s open-source based, enterprise ready platform unifies all the functionality you need to shift testing left - and right. Use our intuitive UI to create tests or reuse your existing scripts and run them at scale as part of your continuous testing strategy. Test and generate detailed reporting and see historic trends. Spend more time innovating & less time maintaining your toolchain. Continuous testing is key to delivering with quality, volume, and velocity. But integrating, maintaining, learning and switching between multiple tools wastes valuable time and resources. BlazeMeter makes it easy with a super intuitive platform that does it all. BlazeMeter delivers complete shift left testing, so you can wow the marketplace with innovation. BlazeMeter provides all the components you need for shift left continuous testing. Work with CLIs, APIs, UI, open source tools, and more. Save HUGE time with setup, maintenance, learning, and day to day use.

Starting Price: $149 per month

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15

RapidAPI

RapidAPI

RapidAPI Testing is a functional API testing and monitoring solution that provides an intuitive UX, support for any API type, and integration with the RapidAPI Marketplace and Enterprise Hub. RapidAPI Testing enables users and enterprises to: Ensure API Functionality – Easily create intricate functional tests for deep validation of APIs. Centralize Monitoring – Monitor and manage API tests across multiple geographies. Improve Efficiency – Integrate to the CI/CD pipeline, collaborate across teams, and natively integrate with the RapidAPI Marketplace and Enterprise Hub. RapidAPI Testing enables you to create customizable functional test flows that provide deep validation of REST, SOAP, and GraphQL APIs. An easy-to-use interface offers users three options for test generation, enabling developers and non-developers to create visual, automated, or code-based test generation.

Starting Price: $59 per user per month

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16

Checkly

Pink Robots

Monitor the status and performance of your API endpoints & vital site transactions from a single, simple dashboard. Checkly is an active reliability platform that brings together the best of end-to-end testing and active monitoring to serve modern, cross-functional DevOps teams. With a focus on JavaScript-based Open Source tech stacks, Checkly is easy to get started with and seamlessly integrates into your development workflow. Checkly is the API & E2E monitoring platform for the modern stack: programmable, flexible and loving JavaScript. Monitor and validate your crucial site transactions. Take screenshots and get instant insights into what's working and what's not. Coding browser click-flows used to be hard. Not anymore. Use modern open source frameworks like Playwright and Puppeteer to automate your flows. Run your checks in 20 locations worldwide. Make sure your APIs always responds quickly and with the correct payload.

Starting Price: $0.80 /10k API check runs

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17

Tigmat

Tigmat

Tigmat is a test automation tool, that allows you to record your tests and run them without having to write a single line of code. Tigmat supports Web, Android, Android Web, and API applications. Providing you with both a Web Recorder and an Android Recorder. By using these tools you don’t have to bother with code, even though you can change anything manually. Test Execution is supported on more than 60 Real Android Devices, Windows, Linux, Chrome, Firefox, and Edge for the best coverage. The best thing is there is a free plan, you simply sign up and can use all features to decide if Tigmat works for you. Every test execution is recorded as a video you can watch. CICD integration and user management are some of the many features provided. Try Tigmat now and discover how our tool can help you achieve your goals.

Starting Price: €199 per month

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18

One APIMarketplace

DigitalAPICraft

Publish, consume, collaborate, accelerate your API journey, and enhance developer experience with our enterprise-grade, API platform-agnostic One APIMarketplace. Reduces API sprawl and API complexities through the operationalization of APIs, making them discoverable, consumable, easy to access, easy to collaborate, and more. One APIMarketplace brings down the time to market by effectively increasing the API adoption, through ease of access, API usage, and performance insights to boost the API consumption. Empower developers with intuitive documentation, community engagement, resources, SDKs, and sandboxes to accelerate API adoption. One APIMarketplace streamlines the discovery and usage of your APIs, guaranteeing a smooth and hassle-free experience for developers and businesses alike. Access comprehensive documentation and test APIs in a sandbox before integration. Gain insights into API usage, performance, and user behavior with our analytics dashboard.

Starting Price: $99 per month

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19

Katalon Studio

Katalon

An all-in-one test automation solution Get started in no time, scale up with no limit, for any team, at any level. Katalon Studio Robust test generation on all platforms Productive IDE to generate automated tests easily for all platforms and OSs, regardless of application complexity. Powerful recording utility for effortlessly storing all UI elements to maximize reusability. Codeless experience for beginners. Infinite testing extension for experts. Set Up Projects Built-in project templates Start immediately with ready-made templates, test case libraries, keywords, and object repositories. All kinds of end-to-end testing in one place Uniquely perform web, mobile, API, and desktop testing – all in a single project.

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20

Eggplant

Keysight Technologies

At Eggplant we empower organizations to create amazing digital experiences. We help businesses to test, monitor and analyze their end-to-end customer experience and continuously improve their business outcomes. Companies worldwide use Eggplant to surpass competitors, boost productivity, and delight customers. How? By dramatically enhancing the quality, responsiveness, and performance of their software applications across different interfaces, platforms, browsers, and devices - including mobile, IoT, and desktop — in agile, DevOps, and innovative application and data environments. As software release cycles accelerate, manual testing can't keep up. AI automatically discovers user journeys, hunts for bugs and performs image-based UI tests from the user POV. Build better software with fast, broad, accurate AI-powered testing. To keep up with DevOps, continuous testing is key, streamlining development and automating the testing process.

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21

PFLB

PFLB

PFLB is an AI-powered load testing platform where you can simulate massive traffic to your websites, and applications. It’s easy to use and super helpful for teams that want to ensure their product is ready to scale. Features: Realistic testing with scenario-based traffic simulation. Importing your production load profile with Google Analytics integration. Easy scripting with an intuitive no-code editor. Executing advanced JMeter scenarios at scale. Resolving bottlenecks with AI-powered performance insights. Discovering load testing results with Grafana dashboards. Protocols: HTTP, HTTPS, gRPC, JDBC, JMS, AMQP, MQTT, Kafka.

Starting Price: $50/month

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22

Runscope

Runscope

An API Monitoring (Runscope) API test is a group of one or more HTTP requests executed sequentially to evaluate the uptime, performance and correctness of an API. For each step in the test, you can define Assertions to validate response data and Variables to extract data to be used in subsequent requests. A test Passes if all the assertions pass. A test Fails if any assertion fails, or another error is encountered, such as a network connection problem. Your customers shouldn’t be the ones telling you about downtime and breakages. Runscope supports the notification tools you already use, like PagerDuty, Slack, HipChat, email, webhooks and more. Proactively monitor service performance to quickly catch and debug API problems fast. Stay ahead of intermittent failures before they become major issues with the API Dashboard and daily API Performance Report. Verify that the structure and content of your API calls meets your expectations. Powerful and flexible assertions give you total control.

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23

ContextQA

ContextQA

ContextQA is a groundbreaking product that empowers organizations to enhance their automation test coverage, elevate software quality, expedite product delivery, and significantly curtail expenses related to maintaining software quality through the utilization of AI-driven SaaS solutions. AI agents will transform your manual test cases and user stories into automated test cases. ContextQA collects evidence and performs root-cause analysis while reporting a bug. ContextQA identifies critical user paths and pinpoints gaps in the software testing process. Complete end-to-end testing, including contract testing, eliminates the need for separate front-end and back-end testing tools. Test and identify glitches, enhance performance, and guarantee seamless user experiences on a plethora of browsers, mobile devices, and OS. ContextQA simplifies the process of incorporating test cases with minimal effort, enabling rapid expansion of automation coverage for your products and services.

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24

Stellar

Vstellar

Speed up your testing processes with Stellar’s low-code automation platform. Enhance efficiency, minimize errors, and achieve smarter software testing with effortless solutions for UI, API, mobile, performance, and accessibility testing. Empower your team to test more and stress less with effortless integration and advanced analytics.

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