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Home / Effective Strategies / Top 12 Performance Testing Tools(Open Source)

Top 12 Performance Testing Tools(Open Source)

Performance testing is a testing method used to evaluate the performance of software, systems, or devices. This post will show you the pros and cons of commonly used performance testing tools on the market.

There are various types of testing performed in software development, including functional testing, usability testing, security testing, and performance testing. Performance testing is crucial for ensuring applications can handle expected user loads and maintain optimal performance. With ever-increasing demand for robust and scalable apps, developers and testers rely on performance testing tools.

This article provides an overview of the top 12 open-source performance testing tools widely used by professionals. From Apache JMeter to Locust, we'll explore the key features and strengths of each tool. Let's move on.

What is Performance Testing?

Performance testing uses automated tools to simulate normal, peak, and abnormal loads, assessing various performance indicators such as efficiency, resource usage, stability, security, compatibility, scalability, and reliability.

Its goal is to ensure post-release performance meets user needs, playing a vital role in software quality assurance. In essence, it simulates production pressures to verify if the system meets performance requirements under specific conditions.

Performance Testing Types:

Here we will briefly introduce the two most commonly used types of performance testing:

  1. Load Testing: This is the most widely used performance testing type. Load testing evaluates how a system performs under a specific expected load. It determines the system's response times, throughput, and resource utilization when multiple users or processes access it concurrently. Load testing helps identify performance bottlenecks and ensure the system can handle the anticipated user load.
  2. Stress Testing: Stress testing is another commonly used performance testing approach. It involves subjecting the system to workloads beyond its specified capacity or resources to determine its breaking point. Stress testing helps identify the maximum operating capacity of the system and uncover any potential stability issues or failures under extreme conditions.

If you want to know more about performance testing, view this guide to learn more.

Performance Testing Guide: All You Need to Know About
Looking to learn more about performance testing? This comprehensive guide has got you covered! From the basics to advanced concepts, we cover everything you need to know to get started with performance testing.

12 Performance Testing Tools for free

Apache JMeter

Apache JMeter is a Java framework that performs various load, performance, and functional tests. It supports multiple protocols and technologies, including web applications, databases, FTP, SMTP, SOAP, REST, etc. It can help testers easily design, execute, and analyze test cases.

Website: https://jmeter.apache.org/


Pros of Apache JMeter:

  • Open source and free: JMeter is an open-source performance testing tool, meaning users can use it for free without any licensing fees.
  • Platform independent: JMeter is developed in Java and can run on different operating systems and hardware environments, making it highly compatible and portable.
  • Rich in features: JMeter supports various testing scenarios and functions, including load testing, stress testing, functional testing, distributed testing, assertion, and validation, etc.

Cons of Apache JMeter:

  • Steep learning curve: Although JMeter provides a graphical user interface, it requires learning specific terms and operations, which can be challenging for some users.
  • Not suitable for complex scenarios: While JMeter supports various protocols and scenarios, it may require high technical expertise and knowledge for certain complex testing scenarios, such as complex web applications or distributed systems.


Apidog is an integrated collaboration platform that combines API documentation, debugging, mock testing, and testing. It can help you design, develop, and test APIs quickly, improve development efficiency, and supports HTTP, SOAP, WebSocket, and other protocols.

Testing Results


LoadRunner is a leading performance testing tool in the industry, developed by Hewlett-Packard Enterprise. It supports multiple protocols and technologies, including web applications, databases, ERP systems, and mobile applications, and provides a visual test script editor, test scenario design tool, and analysis reporting functions.

Website: https://www.microfocus.com/products/loadrunner-load-testing/overview


Pros of LoadRunner

  • Powerful functionality: LoadRunner supports multiple protocols and technologies, including web applications, databases, ERP systems, mobile applications, etc., and can perform various types of performance testing.
  • Visual script editor: LoadRunner provides an intuitive script editor that allows testers to create and edit test cases quickly and accurately through a graphical interface.
  • Reporting and analysis capabilities: LoadRunner offers rich analysis tools and reports that enable testers to analyze and interpret test results in detail, allowing them to better understand application performance bottlenecks and issues.
  • Strong concurrency simulation capability: LoadRunner can simulate a large number of concurrent users and support multiple virtual users simultaneously, allowing it to complete large-scale performance testing in a relatively short amount of time.

Cons of LoadRunner

  • Expensive: LoadRunner is a commercial software that requires payment for purchase and use, making it relatively expensive compared to other open-source tools.
  • Steep learning curve: Similar to JMeter, LoadRunner requires learning its specific terminology and operations, which comes with a learning curve.
  • High hardware requirements: LoadRunner requires high hardware specifications, including a large amount of memory, processor, and storage space, which may not be friendly for some small teams or individual testers.
  • Only runs on Windows: LoadRunner can only run on the Windows operating system, limiting its portability and compatibility.


Gatling is a performance testing tool developed in the Scala language, which can be used for load testing and performance testing of web applications and WebSocket applications. It provides a simple and easy-to-use DSL language, which can help testers quickly write test cases and provides real-time statistical data and HTML reports, etc.



Pros of Gating

  • Efficient performance: Gatling adopts an asynchronous non-blocking IO model, which can support high-concurrency performance testing and has outstanding performance.
  • Support for multiple protocols: Gatling supports multiple protocols, including HTTP, JMS, JDBC, SSH, etc., which can meet different testing needs.
  • Powerful reporting functionality: Gatling provides rich reporting functionality, which can intuitively display test results, facilitating performance issue analysis and optimization.
  • Open-source and free: Gatling is an open-source performance testing tool that can be used for free.

Cons of Gatling

  • A server-side tool with pure code and no visual configuration interface, steep learning curve.
  • Relatively weak community resources: Compared with older performance testing tools such as JMeter and LoadRunner, the user group and community resources of Gatling are relatively small, so users may encounter some problems during use.
  • Incomplete documentation: Gatling's official documentation is relatively incomplete, and users need to search for information and learn on their own.
  • Some functions are not perfect: Although Gatling supports multiple protocols, it may be incomplete in some details and requires users to extend and optimize on their own.


k6 is a developer-centric, open-source load testing tool designed for testing the performance of back-end infrastructure. It is built with Go and JavaScript, integrating well into most developers' workflows.

k6 is designed to be easy to use and highly scalable, allowing users to start including performance testing in their continuous integration pipelines. It provides a clean scripting API and supports distributed and cloud execution for simulating a large number of concurrent users.

Key Features:

  • Clean scripting API
  • Distributed and Cloud Execution
  • REST API orchestration ability
  • Browser-level front-end performance testing with the new xk6 extension


Tsung is an open-source, multi-protocol distributed load testing tool. It is designed to simulate a large number of concurrent users and test the performance of various protocols, including HTTP, XMPP, LDAP, and more.

One of the key features of Tsung is its ability to monitor client-side metrics, such as CPU, memory, and network traffic, in addition to server-side metrics. This provides a more comprehensive view of the system's performance under load.

Tsung includes an HTTP recorder for capturing user interactions and generating test scripts automatically. It also provides HTML reports and graphs for visualizing and analyzing test results. Tsung's support for multiple protocols makes it a versatile tool for testing various types of applications and services.

Key Features:

  • HTTP recorder
  • HTML reports and graphs
  • Support for protocols like HTTP, XMPP, LDAP, etc.


NeoLoad is a powerful performance testing tool mainly used to test the performance and scalability of web, mobile, and enterprise applications.



Pros of NeoLoad:

  • Powerful testing capabilities: NeoLoad offers various testing capabilities, including load testing, stress testing, stability testing, capacity planning, etc., to cater to different testing needs.
  • Easy to use: NeoLoad has a user-friendly interface, and the testing script writing and execution process is straightforward and easy to understand.
  • Support for multiple protocols: NeoLoad supports multiple protocols, including HTTP, HTTPS, SOAP, REST, JDBC, JMS, FTP, etc., to cater to different testing needs.
  • Support for multiple platforms and devices: NeoLoad can run tests on different platforms and devices, including Windows, Linux, macOS, iOS, Android, etc.
  • Strong reporting capabilities: NeoLoad provides rich reporting features, which can visually display test results and performance metrics, making it easy to analyze and optimize performance issues.

Cons of NeoLoad:

  • Commercial software: NeoLoad is a commercial performance testing tool that requires payment to use, which may not be friendly for small teams or individual testers.
  • High learning curve: Although NeoLoad is easy to use, it requires a certain learning curve for beginners to become proficient in its testing capabilities and operation.
  • Some functions are not perfect: Although NeoLoad has multiple testing capabilities, some of its functions may not be perfect in certain detailed aspects, requiring users to expand and optimize them on their own.


WebLOAD is a performance testing tool designed for load and stress testing of web applications, providing a user-friendly interface and comprehensive reporting features.

Website: https://www.radview.com/webload-overview/


Pros of WebLOAD

  • Advanced scripting capabilities: WebLOAD offers advanced scripting capabilities that allow users to create complex test scenarios and emulate real user behavior.
  • Built-in integrations with various technologies: WebLOAD supports integration with various technologies including HTTP/HTTPS, SOAP, REST, HTML5, WebSockets, and more.
  • Powerful reporting and analysis tools: WebLOAD provides detailed reports and analysis tools that allow users to identify performance bottlenecks and improve their application's performance.
  • Scalability and load distribution: WebLOAD can simulate large-scale tests and distribute them across multiple load generators to ensure accurate results.
  • User-friendly interface: WebLOAD features a user-friendly interface that makes it easy to use, even for beginners.

Cons of WebLOAD

  • Limited community support: Compared to other performance testing tools, WebLOAD has a relatively small community, which can limit the availability of resources and support.
  • Steep learning curve: WebLOAD's advanced scripting capabilities may require some time to learn and master, making it less accessible for beginners.
  • Expensive licensing fees: WebLOAD is a commercial tool with high licensing fees, which can make it difficult for smaller teams or individual testers to afford.
  • Limited integration with non-web technologies: While WebLOAD offers robust support for web technologies, it may not be the best choice for testing applications that rely heavily on non-web technologies such as mainframes or databases.


LoadNinja is a cloud-based load-testing tool that uses real web browsers to simulate user traffic and behavior for highly accurate test results.

Website: https://loadninja.com/

Pros of LoadNinja

  • Record and replay test scripts: LoadNinja allows you to record and replay test scripts, making it easy to create and execute performance tests without requiring a lot of coding skills.
  • Integrated load testing and A/B testing: LoadNinja includes A/B testing capabilities, allowing you to compare the performance of two or more versions of your website or application under load.
  • Real browser-based testing: LoadNinja uses real browsers to simulate user behavior, which provides more accurate results than other testing tools that use simulated browser behavior.
  • Cloud-based testing: LoadNinja is a cloud-based testing tool, which means you don't need to set up and maintain your own testing infrastructure.

Cons of LoadNinja

  • Limited protocol support: LoadNinja only supports HTTP and HTTPS protocols, which may not be suitable for testing applications that use other protocols.
  • Limited customization options: While LoadNinja is easy to use, it may not offer the same level of customization and flexibility as other performance testing tools.
  • Limited community support: LoadNinja is a relatively new tool with a small user base, which means that community support may be limited compared to more established tools.
  • Cost: LoadNinja is a paid tool, which may not be suitable for small teams or individual testers with limited budgets.


Locust is a Python-based open-source load testing tool that allows developers to write user behavior in code, making it highly flexible and customizable.

Website: https://locust.io/

Pros of Locust

  • Easy to use: Locust's user-friendly interface and straightforward syntax make it easy for even non-technical users to create load-testing scenarios.
  • Scalable: Locust can simulate thousands of concurrent users with ease, allowing you to test the scalability of your application.
  • Distributed testing: Locust supports distributed testing, which allows you to simulate even more concurrent users across multiple machines.
  • Open source: Locust is an open-source tool and can be used for free.

Cons of Locust

  • Limited protocol support: While Locust supports HTTP, it lacks support for other protocols such as FTP, JDBC, JMS, etc.
  • No built-in reporting: Locust doesn't come with built-in reporting, so users need to rely on third-party integrations to generate reports.
  • Steep learning curve: Although Locust's syntax is straightforward, it still requires users to have a basic understanding of Python, which may pose a challenge for some users.


Taurus is an open-source automation tool that supports multiple testing frameworks and can be easily integrated into existing DevOps workflows for scalable and efficient testing.

Website: https://gettaurus.org/

Pros of Taurus

  • Supports multiple testing tools and languages: Taurus can work with a variety of testing tools and languages, including JMeter, Gatling, Selenium, and more.
  • Open-source and free: Taurus is an open-source tool that can be used for free, making it an attractive option for budget-conscious users.
  • Provides an easy-to-read YAML configuration: Taurus uses a YAML-based configuration, which is easy to read and write, allowing users to configure tests quickly and efficiently.
  • Offers flexible and powerful reporting: Taurus provides comprehensive reports that can be customized to meet different testing needs, including graphical charts, pass/fail statistics, and more.

Cons of Taurus

  • Limited documentation: Taurus documentation is not as comprehensive as other tools, and users may need to rely on community support to find solutions to issues.
  • Limited user community: Taurus is a relatively new tool and has a smaller user community compared to other popular performance testing tools, which may affect support and updates.
  • Steep learning curve: Taurus requires some knowledge of the YAML configuration language, as well as an understanding of how different testing tools and languages work, which may be challenging for new users.
  • May require additional tools for complex testing scenarios: Taurus may not be sufficient for complex testing scenarios that require advanced scripting or customization, and users may need to integrate other testing tools to achieve desired results.


Artillery is an open-source load-testing tool that supports HTTP, WebSocket, and Socket.io protocols and can be used to test any system with a public HTTP or WebSocket interface.

Website: https://artillery.io/

Pros of Artillery

  • Flexible and easy-to-use: Artillery offers a flexible configuration and scripting system that makes it easy to write and execute complex test scenarios.
  • Extensible and customizable: Artillery's open-source nature allows users to easily extend its functionality through plugins and custom JavaScript code.
  • Real-time monitoring and reporting: Artillery provides real-time monitoring and reporting of test results, including metrics such as response times and error rates.
  • Multiple protocol support: Artillery supports multiple protocols, including HTTP, WebSocket, and Socket.io, making it a versatile tool for testing various types of applications.
  • Free and open source: Artillery is a free and open-source tool, making it accessible to anyone who needs to conduct performance testing.

Cons of Artillery

  • Limited GUI interface: Artillery is a command-line tool and lacks a graphical user interface, which may be a challenge for some users who prefer visual tools.
  • Limited community support: While Artillery has an active community of users, it may not have the same level of support and resources as some other tools, which can make problem-solving more difficult.
  • No built-in reporting: Artillery does not have built-in reporting features, which may require users to export data to third-party tools for further analysis.
  • Limited documentation: Artillery's documentation is not as comprehensive as some other tools, which can make it more challenging for users to get started and troubleshoot issues.

How Does Performance Testing Tools Work?

Performance testing involves diverse methodologies to assess a software system's behavior under varied conditions.

Load testing concentrates on measuring response times and pinpointing bottlenecks amid anticipated user loads. Stress testing scrutinizes the system's resilience, pushing it to capacity limits under extreme conditions.

Soak testing validates the system's endurance over sustained loads, identifying resource leaks and performance degradation. Spike testing examines how the system copes with abrupt load changes by rapidly altering user numbers. These testing methods collectively offer a thorough evaluation of an application's performance attributes.


In conclusion, based on the above comparison of performance testing tools, Apidog is a highly recommended option for those seeking a tool with a low learning curve and broad platform support.

JMeter and NeoLoad are also strong contenders due to their extensive functionality and support for all platforms. LoadRunner and WebLOAD are more limited in platform support but offer high levels of functionality.

LoadNinja, Locust, Taurus, and Artillery all offer medium levels of functionality and platform support, making them viable options for certain testing needs. Ultimately, the choice of tool will depend on individual requirements and preferences.

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