Test coverage is a metric that measures how much of your codebase is exercised by tests, providing insight into the effectiveness of your testing efforts. In this blog, we’ll focus on API projects, exploring the types of tests suited for code coverage, realistic goals (and tools to help achieve them), and the minimum coverage needed to reap the benefits of your tests.

Testing your code—down to individual lines—is a critical practice in modern software development. It helps ensure applications remain reliable, stable, and maintainable, all while balancing practical constraints.