List of the Top 25 Free Code Coverage Tools in 2025

Sahi Pro is a comprehensive suite of automation tools designed for various platforms, including web applications, web services, Windows desktop, and Java applications. Key features of Sahi Pro encompass automatic waits, recorders, and an accessor spy, as well as an integrated frame and editor, parallel playback capabilities, and both automatic reporting and logging functionalities. In addition, it is capable of reducing the time and effort required for test automation by up to 70%. With a growing reputation, Sahi Pro has gained the trust of over 400 companies globally, establishing itself as a favored choice for test automation, especially in agile development environments. Furthermore, its user-friendly interface and robust capabilities make it an attractive option for teams looking to streamline their testing processes.

JetBrains' IntelliJ IDEA serves as a powerful IDE specifically tailored for expert Java and Kotlin programming. It enhances your productivity and simplifies the process of writing high-quality code. Crafted to ensure you complete your tasks efficiently, it encompasses all the necessary tools and resources for utilizing the latest technologies. With its user-friendly interface and seamless workflow, it allows you to code confidently while prioritizing your privacy and security. This combination of features makes IntelliJ IDEA a top choice for developers who value both efficiency and safety in their work environment.

Boost your efficiency by ensuring that only top-notch code is deployed, as SonarQube Cloud (formerly known as SonarCloud) effortlessly assesses branches and enhances pull requests with valuable insights. Detecting subtle bugs is crucial to preventing erratic behavior that could negatively impact users, while also addressing security vulnerabilities that pose a risk to your application, all while deepening your understanding of application security through the Security Hotspots feature. You can quickly start utilizing the platform directly from your coding environment, allowing you to take advantage of immediate access to the latest features and enhancements. Project dashboards deliver essential insights into code quality and release readiness, ensuring that both teams and stakeholders are well-informed. Displaying project badges highlights your dedication to excellence within your communities and serves as a testament to your commitment to quality. Recognizing that code quality and security are vital throughout your entire technology stack—covering both front-end and back-end development—we support an extensive selection of 24 programming languages, including Python, Java, C++, and more. As the call for transparency in coding practices increases, we encourage you to join this movement; it's entirely free for open-source projects, presenting a valuable opportunity for all developers! Additionally, by engaging with this initiative, you play a role in a broader community focused on elevating software quality and fostering collaboration among developers. Embrace this chance to enhance your skills while contributing to a collective mission of excellence.

Improve your coding standards and enhance the efficacy of your code review process by embracing better coding habits. Codecov provides an array of integrated tools that facilitate the organization, merging, archiving, and comparison of coverage reports in a cohesive manner. For open-source initiatives, this service is available at no cost, while paid options start as low as $10 per user each month. It accommodates a variety of programming languages, such as Ruby, Python, C++, and JavaScript, and can be easily incorporated into any continuous integration (CI) workflow with minimal setup required. The platform automates the merging of reports from all CI systems and languages into a single cohesive document. Users benefit from customized status notifications regarding different coverage metrics and have access to reports categorized by project, directory, and test type—be it unit tests or integration tests. Furthermore, insightful comments on the coverage reports are seamlessly integrated into your pull requests. With a commitment to protecting your information and systems, Codecov boasts SOC 2 Type II certification, affirming that their security protocols have been thoroughly evaluated by an independent third party. By leveraging these tools, development teams can substantially enhance code quality and optimize their workflows, ultimately leading to more robust software outcomes. As a result, adopting such advanced tools not only fosters a healthier coding environment but also encourages collaboration among team members.

DeepSource simplifies the task of detecting and fixing code problems during reviews, addressing potential bugs, anti-patterns, performance issues, and security threats. Its integration with Bitbucket, GitHub, or GitLab is quick and easy, taking less than five minutes to set up, which adds to its convenience. It accommodates a variety of programming languages, including Python, Go, Ruby, and JavaScript, and extends its support to all major languages alongside Infrastructure-as-Code features, secret detection, and code coverage. This comprehensive support means DeepSource can be your go-to solution for safeguarding your code. By leveraging the most sophisticated static analysis platform, you ensure that bugs are caught before they reach production. With an extensive set of static analysis rules unmatched in the industry, your team will have a centralized hub for effectively monitoring and maintaining code quality. Additionally, DeepSource automates code formatting, helping to keep your CI pipeline free from style-related disruptions. It also offers the capability to automatically generate and apply fixes for identified problems with minimal effort, significantly boosting your team's productivity and efficiency. Moreover, by streamlining the code review process, DeepSource enhances collaboration among developers, leading to higher quality software outcomes.

With a wide range of tools and APIs provided by top cloud service providers, creating services in Go has become more straightforward than ever. The language boasts a rich set of open-source libraries, alongside its robust standard library, making it an excellent choice for developing quick and advanced command-line interfaces. Go's impressive memory management and support for various integrated development environments further bolster its ability to power fast and scalable web applications. Additionally, its rapid compilation speed and clean syntax, coupled with built-in documentation and formatting features, are specifically designed to cater to the needs of DevOps experts and site reliability engineers. This discussion delves deeply into all aspects of Go. Whether you are starting a new project or aiming to enhance your existing Go expertise, a well-structured interactive introduction is available, divided into three distinct parts. Each segment includes practical exercises that reinforce your learning, while the Playground feature enables users to write and execute Go code directly within a browser, with immediate compilation and linking occurring on our servers. This interactive learning method not only makes mastering Go effective but also turns the process into an enjoyable experience. Furthermore, the community surrounding Go offers valuable resources and support, enriching your journey as you explore this powerful programming language.

To utilize PHPUnit effectively, the dom and json extensions must be enabled, which are usually active by default, along with the pcre, reflection, and spl extensions that are standard and cannot be disabled without altering PHP's build system or source code. Furthermore, for generating code coverage reports, it's essential to have the Xdebug extension (version 2.7.0 or later) and the tokenizer extension installed, while the creation of XML reports relies on the xmlwriter extension. Engaging in unit testing is a vital practice for developers, allowing them to identify and rectify bugs, improve code quality, and document the software units under examination. Ideally, these unit tests should cover every possible execution path within a given program to ensure comprehensive validation. Typically, each unit test corresponds to a specific execution path within a function or method. However, it's crucial to acknowledge that a test method may not operate as a completely standalone unit; often, there are subtle interdependencies among various test methods due to the underlying implementation of the test scenario. This web of connections can pose significant challenges in maintaining the integrity and reliability of tests, complicating the overall testing process. Consequently, developers must remain vigilant about these dependencies to ensure their tests are both effective and trustworthy.

This module presents metrics specifically designed for code coverage in Perl, illustrating the degree to which tests interact with the codebase. By employing Devel::Cover, developers can pinpoint areas of their code that lack tests and determine which additional tests are needed to improve overall coverage. In essence, code coverage acts as a useful proxy for assessing software quality. Devel::Cover has achieved a notable level of reliability, offering a variety of features characteristic of effective coverage tools. It generates comprehensive reports detailing statement, branch, condition, subroutine, and pod coverage. Typically, the information regarding statement and subroutine coverage is trustworthy, although branch and condition coverage might not always meet expectations. For pod coverage, it utilizes Pod::Coverage, and if the Pod::Coverage::CountParents module is available, it will draw on that for more thorough analysis. Additionally, the insights provided by Devel::Cover can significantly guide developers in refining their testing strategies, making it a vital resource for enhancing the robustness of Perl applications. Ultimately, Devel::Cover proves to be an invaluable asset for Perl developers striving to elevate the quality of their code through improved testing methodologies.

LuaCov is a user-friendly tool designed for coverage analysis of Lua scripts. When a Lua script is executed with the luacov module enabled, it generates a statistics file that records the number of times each line in the script and its related modules is executed. This file is subsequently analyzed by the luacov command-line tool, which produces a report that helps users pinpoint any code paths that have not been executed, a critical factor in evaluating the effectiveness of a test suite. The tool also provides numerous configuration options, with global defaults specified in src/luacov/defaults.lua. For those requiring tailored configurations specific to their projects, a Lua script can be created that either defines options as global variables or returns a table of particular settings, which should then be saved as .luacov in the project's root directory where luacov runs. For example, a configuration might indicate that only the foo module and its submodules, which are situated in the src directory, should be part of the coverage analysis. This level of customization empowers developers to adjust their coverage analysis to meet the unique requirements of their projects. Consequently, LuaCov not only enhances testing efficiency but also promotes better code quality through improved coverage insights.

Tarpaulin is a specialized tool aimed at reporting code coverage within the cargo build system, taking its name from a robust fabric commonly used to safeguard cargo on ships. Currently, it provides line coverage effectively, though there may be occasional minor inaccuracies in its reporting. Considerable efforts have been invested in improving its compatibility with a wide range of projects, but unique combinations of packages and build configurations can still result in potential issues, prompting users to report any inconsistencies they may find. The roadmap also details forthcoming features and enhancements that users can look forward to. On Linux platforms, Tarpaulin relies on Ptrace as its primary tracing backend, which is constrained to x86 and x64 architectures; however, users can switch to llvm coverage instrumentation by designating the engine as llvm, which is the standard approach for Mac and Windows users. Moreover, Tarpaulin can be implemented within a Docker environment, providing a convenient option for those who prefer not to operate Linux directly yet still wish to take advantage of its functionality locally. This adaptability makes Tarpaulin an essential asset for developers focused on enhancing their code quality through thorough coverage analysis, thereby ensuring a more robust and reliable software development process. As a result, it stands out as a comprehensive solution in the realm of code coverage tools.

grcov is a utility designed to collect and unify code coverage information from multiple source files. It can effectively process .profraw and .gcda files generated by llvm/clang or gcc compilers. Furthermore, grcov supports lcov files for JavaScript coverage along with JaCoCo files for Java projects. This adaptable tool works seamlessly across various operating systems such as Linux, macOS, and Windows, ensuring that developers from diverse environments can utilize it. By leveraging its capabilities, teams can significantly improve their analysis of code quality and test coverage, leading to better software outcomes. Its broad compatibility and robust functionality make it an essential asset for any development workflow.

Kcov is a versatile code coverage testing tool designed for FreeBSD, Linux, and OSX, supporting a range of compiled languages, Python, and Bash. Originally based on Bcov, Kcov has evolved into a more powerful solution, boasting a wide range of features that surpass those of the original tool. Like Bcov, Kcov utilizes DWARF debugging information from compiled applications, allowing for the collection of coverage data without requiring particular compiler flags. This capability simplifies the code coverage evaluation process, enhancing accessibility for developers working in different programming languages. Additionally, Kcov's continuous improvement ensures that it remains relevant and effective in meeting the demands of modern software development.

An easy-to-use command-line tool created to collect test coverage information from Dart VM tests, serving as a crucial resource for developers needing local coverage reports during their project development. This utility simplifies the analysis of test performance and allows developers to effortlessly track the test coverage of their code as they work, ensuring they maintain a high standard of quality in their applications. By facilitating real-time monitoring, it enhances the overall testing workflow and encourages better coding practices.

Coverage provides a suite of tools designed to collect, process, and format coverage data tailored for Dart programming. The Collect_coverage function fetches coverage metrics in JSON format directly from the Dart VM Service, and the format_coverage function subsequently converts this JSON data into either the LCOV format or a more user-friendly, nicely formatted version for improved readability. These tools significantly improve the analysis of code coverage, enabling developers to gain deeper insights into their code's performance and quality. Ultimately, this functionality supports better decision-making in the development process.

The main emphasis needs to be placed on improving the visual appeal of the report user interface and optimizing the Maven configuration steps. Furthermore, it is crucial to integrate the plugin instrumentation settings within the child projects, while also guaranteeing that the report merging settings are established at the parent project level. By adopting this strategy, a more unified and intuitive user experience can be achieved, fostering greater efficiency and satisfaction among users.

Cloverage primarily utilizes clojure.test for conducting tests, but it can be switched to midje by using the --runner :midje option. In previous versions of Cloverage, it was necessary to wrap midje tests within clojure.test's deftest, a limitation that has been lifted in the most recent updates. If you prefer to work with eftest, you can easily do so by applying the --runner :eftest flag. Furthermore, you have the ability to customize the testing runner through the :runner-opts option with a map in your project configuration. It's important to keep in mind that various other testing frameworks may provide their own compatibility with Cloverage, so checking their documentation is advisable for further insights. This level of adaptability not only enhances your testing experience but also empowers you to align it more closely with your specific development requirements. Thus, you can create a more efficient and tailored workflow for your testing processes.

To generate test coverage reports for Xcode projects and seamlessly incorporate them into your continuous integration (CI) workflow, ensure that you enable the coverage feature by selecting the "Gather coverage data" option within the scheme settings. This configuration will facilitate the monitoring of code quality and verify that your tests adequately cover all critical areas of your application, ultimately enhancing your development efficiency and effectiveness. Additionally, regularly reviewing these reports can provide insights that help improve your testing strategy over time.

NCover Desktop is a specialized tool for Windows that aims to collect code coverage information specifically for .NET applications and services. After gathering this data, users can access a rich array of charts and metrics via a web-based interface, allowing for in-depth analysis down to individual lines of code. Moreover, there is an option to incorporate a Visual Studio extension called Bolt, which enhances the code coverage experience by showcasing unit test results, execution durations, branch coverage representations, and highlighted source code within the Visual Studio IDE itself. This improvement in NCover Desktop greatly boosts the user-friendliness and capability of code coverage tools. By assessing code coverage during .NET testing, NCover provides valuable insights into the execution of code segments, along with accurate metrics regarding unit test coverage. Tracking these metrics consistently enables developers to maintain a dependable measure of code quality throughout the development cycle, ultimately fostering the creation of a stronger and thoroughly tested application. The implementation of such tools not only elevates software reliability but also enhances overall performance. Consequently, teams can leverage these insights to make informed decisions that contribute to the continuous improvement of their software projects.

JaCoCo is a free library for Java code coverage, crafted by the EclEmma team, and has seen continuous improvement over the years based on insights gained from other libraries. The master branch of JaCoCo undergoes automatic building and publishing, which guarantees that each build complies with test-driven development principles, ensuring full functionality. Users can refer to the change history for the latest features and bug fixes. In addition, metrics related to the current JaCoCo implementation can be accessed on SonarCloud.io, providing further insights into its performance. JaCoCo can be easily integrated with various tools, allowing users to take advantage of its capabilities right from the start. Contributions aimed at enhancing its implementation and introducing new features are welcomed from the community. While there are several open-source coverage solutions for Java, the experience from developing the Eclipse plug-in EclEmma has highlighted that many existing tools are not ideally designed for integration purposes. One major drawback is that many of these tools cater to specific environments, like Ant tasks or command line interfaces, and they often lack a comprehensive API that would allow for embedding in a variety of settings. This limitation in flexibility frequently prevents developers from effectively utilizing coverage tools across multiple platforms, creating a gap that JaCoCo aims to fill with its adaptable architecture. Ultimately, JaCoCo seeks to provide a more versatile solution for developers looking for robust code coverage tools.

Distributing your focus wisely between application development and the creation of test code is crucial. For those using Java and Groovy, leveraging an advanced code coverage tool becomes imperative, with OpenClover being particularly noteworthy as it assesses code coverage while also collecting more than 20 diverse metrics. This tool effectively pinpoints the areas within your application that lack adequate testing and merges coverage information with these metrics to reveal the most at-risk sections of your code. Furthermore, its Test Optimization capability tracks the connections between test cases and application classes, allowing OpenClover to run only the tests that are relevant to recent changes, which significantly boosts the efficiency of the overall test execution process. You might question the value of testing simple getters, setters, or code that has been generated automatically. OpenClover shines with its versatility, permitting users to customize coverage assessments by disregarding certain packages, files, classes, methods, and even specific lines of code. This level of customization empowers you to direct your testing efforts toward the most vital aspects of your codebase. In addition to tracking test outcomes, OpenClover delivers a comprehensive coverage analysis for each individual test, providing insights that ensure you fully grasp the effectiveness of your testing endeavors. This emphasis on detailed analysis can lead to substantial enhancements in both the quality and dependability of your code, ultimately fostering a more robust software development lifecycle. Through diligent use of such tools, developers can ensure that their applications not only meet functional requirements but also maintain high standards of code integrity.

The JCov open-source project was established to gather quality metrics pertinent to the creation of test suites. By making JCov readily available, the initiative seeks to improve the verification process of regression test executions in the development of OpenJDK. The main objective of JCov is to provide clarity regarding test coverage metrics. Advocating for a standardized coverage tool such as JCov offers advantages to OpenJDK developers by delivering a code coverage solution that progresses alongside developments in the Java language and virtual machine. Completely developed in Java, JCov functions as a tool for evaluating and analyzing dynamic code coverage in Java applications. It encompasses features that assess method coverage, linear block coverage, and branch coverage, while also pinpointing execution paths that go untested. Furthermore, JCov has the capability to annotate the source code of the program with coverage information. This tool is particularly significant from a testing perspective, as it aids in uncovering execution paths and provides insights into how various code segments are utilized during testing. Such comprehensive understanding empowers developers to refine their testing methodologies and elevate the overall quality of their code, ultimately contributing to more robust software development practices.

Achieving simplified JavaScript test coverage is possible with Istanbul, which enhances your ES5 and ES2015+ code by integrating line counters to measure the extent of your unit tests in covering the codebase. The nyc command-line interface works seamlessly with a variety of JavaScript testing frameworks, including tap, mocha, and AVA. By employing babel-plugin-Istanbul, you gain robust support for ES6/ES2015+, ensuring compatibility with popular JavaScript testing tools. Additionally, nyc’s command-line functionalities allow for the instrumentation of subprocesses, providing more comprehensive coverage insights. Integrating coverage into mocha tests is straightforward; simply add nyc as a prefix to your test command. Moreover, nyc's instrument command can be used to prepare source files even beyond the immediate scope of your unit tests. When running a test script, nyc conveniently lists all Node processes spawned during the execution. While nyc typically defaults to Istanbul's text reporter, you also have the option to select different reporting formats to better meet your requirements. Overall, nyc significantly simplifies the journey toward achieving extensive test coverage for JavaScript applications, enabling developers to enhance code quality with ease while ensuring that best practices are followed throughout the testing process. This functionality ultimately fosters a more efficient development workflow, making it easier to maintain high standards in code reliability and performance.

Blanket.js is an intuitive code coverage library for JavaScript that streamlines the processes of installation, usage, and comprehension of code coverage metrics. This versatile tool offers both straightforward operation and the ability to customize features to meet specific needs. By delivering code coverage statistics, Blanket.js enriches your JavaScript testing suite by revealing which lines of your source code are actually being exercised during tests. It accomplishes this through the use of Esprima and node-falafel for code parsing, subsequently inserting tracking lines for further analysis. The library seamlessly integrates with various test runners to generate detailed coverage reports post-test execution. Moreover, a Grunt plugin allows Blanket to operate as a traditional code coverage tool, creating instrumented file versions instead of utilizing live instrumentation. Blanket.js also supports running QUnit-based tests in a headless environment with PhantomJS, providing results directly in the console. Importantly, if any specified coverage thresholds are not met, the Grunt task will fail, reinforcing adherence to quality standards among developers. In summary, Blanket.js is a powerful asset for developers dedicated to achieving and maintaining exemplary test coverage in their JavaScript projects, making it an indispensable tool in the development workflow.

The jscoverage tool is designed to support both Node.js and JavaScript, thereby broadening the scope of code coverage analysis. To make use of this tool, you load the jscoverage module via Mocha, which allows it to work efficiently within your testing environment. When you choose various reporters such as list, spec, or tap in Mocha, jscoverage seamlessly integrates the coverage data into the reports. You can set the type of reporter using covout, which provides options for generating HTML reports and detailed output. The detailed reporting option particularly highlights any lines of code that remain uncovered, displaying them directly in the console for quick reference. While Mocha runs the test cases with jscoverage active, it also ensures that any files specified in the covignore file are not included in the coverage analysis. On top of this, jscoverage produces an HTML report that delivers a full overview of the coverage statistics. It automatically searches for the covignore file in the project's root directory and also manages the copying of excluded files from the source directory to the designated output folder, helping to maintain a tidy and structured testing environment. This functionality not only streamlines the testing process but also enhances clarity by pinpointing which sections of the codebase are thoroughly tested and which need additional focus, ultimately leading to improved code quality.

SimpleCov is a Ruby-based tool utilized for analyzing code coverage, which utilizes Ruby's built-in Coverage library to gather data while presenting a straightforward API that aids in processing results by enabling filtering, grouping, merging, formatting, and effective display. While it is proficient in monitoring the covered Ruby code, it lacks support for popular templating systems such as erb, slim, and haml. For many projects, acquiring a holistic view of coverage outcomes across various testing types, including Cucumber features, is vital. SimpleCov streamlines this process by automatically caching and merging results for report generation, ensuring that the final report encapsulates coverage from all test suites, thus offering a more comprehensive overview of areas needing enhancement. To ensure accurate results, it is crucial to run SimpleCov within the same process as the code being analyzed for coverage. Furthermore, leveraging SimpleCov can significantly improve your development workflow by pinpointing untested code segments, ultimately fostering the creation of more robust applications. This tool not only aids in enhancing code quality but also promotes a culture of thorough testing in development teams.