The latest articles on DEV Community by Martin Komischke (@makom). https://dev.to/makom https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F2463030%2F67f6e464-a8f0-4fbf-ae91-d978a44aba2f.jpeg https://dev.to/makom en Martin Komischke Mon, 30 Mar 2026 13:04:22 +0000 https://dev.to/makom/-2i08 https://dev.to/makom/-2i08 <div class="ltag__link--embedded"> <div class="crayons-story "> <a href="https://dev.to/makom/code-coverage-test-coverage-3hc1" class="crayons-story__hidden-navigation-link">Code Coverage + Test Coverage</a> <div class="crayons-story__body crayons-story__body-full_post"> <div class="crayons-story__top"> <div class="crayons-story__meta"> <div class="crayons-story__author-pic"> <a href="/makom" class="crayons-avatar crayons-avatar--l "> <img src="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F2463030%2F67f6e464-a8f0-4fbf-ae91-d978a44aba2f.jpeg" alt="makom profile" class="crayons-avatar__image" width="745" height="745"> </a> </div> <div> <div> <a href="/makom" class="crayons-story__secondary fw-medium m:hidden"> Martin Komischke </a> <div class="profile-preview-card relative mb-4 s:mb-0 fw-medium hidden m:inline-block"> Martin Komischke <div id="story-author-preview-content-3270540" class="profile-preview-card__content crayons-dropdown branded-7 p-4 pt-0"> <div class="gap-4 grid"> <div class="-mt-4"> <a href="/makom" class="flex"> <span class="crayons-avatar crayons-avatar--xl mr-2 shrink-0"> <img src="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F2463030%2F67f6e464-a8f0-4fbf-ae91-d978a44aba2f.jpeg" class="crayons-avatar__image" alt="" width="745" height="745"> </span> <span class="crayons-link crayons-subtitle-2 mt-5">Martin Komischke</span> </a> </div> <div class="print-hidden"> Follow </div> <div class="author-preview-metadata-container"></div> </div> </div> </div> </div> <a href="https://dev.to/makom/code-coverage-test-coverage-3hc1" class="crayons-story__tertiary fs-xs"><time>Feb 20</time><span class="time-ago-indicator-initial-placeholder"></span></a> </div> </div> </div> <div class="crayons-story__indention"> <h2 class="crayons-story__title crayons-story__title-full_post"> <a href="https://dev.to/makom/code-coverage-test-coverage-3hc1" id="article-link-3270540"> Code Coverage + Test Coverage </a> </h2> <div class="crayons-story__tags"> <a class="crayons-tag crayons-tag--monochrome " href="/t/beginners"><span class="crayons-tag__prefix">#</span>beginners</a> <a class="crayons-tag crayons-tag--monochrome " href="/t/codequality"><span class="crayons-tag__prefix">#</span>codequality</a> <a class="crayons-tag crayons-tag--monochrome " href="/t/programming"><span class="crayons-tag__prefix">#</span>programming</a> <a class="crayons-tag crayons-tag--monochrome " href="/t/testing"><span class="crayons-tag__prefix">#</span>testing</a> </div> <div class="crayons-story__bottom"> <div class="crayons-story__details"> <a href="https://dev.to/makom/code-coverage-test-coverage-3hc1#comments" class="crayons-btn crayons-btn--s crayons-btn--ghost crayons-btn--icon-left flex items-center"> Comments <span class="hidden s:inline">Add Comment</span> </a> </div> <div class="crayons-story__save"> <small class="crayons-story__tertiary fs-xs mr-2"> 1 min read </small> <span class="bm-initial"> </span> <span class="bm-success"> </span> </div> </div> </div> </div> </div> </div> beginners codequality programming testing Martin Komischke Fri, 20 Feb 2026 10:06:19 +0000 https://dev.to/makom/code-coverage-test-coverage-3hc1 https://dev.to/makom/code-coverage-test-coverage-3hc1 <p>Many developers chase high code coverage numbers, believing they signal a well-tested codebase — but that metric alone can be dangerously misleading. This post cuts through the confusion by clearly distinguishing <strong>code coverage</strong> from <strong>test coverage</strong>. Understanding both concepts helps you build a truly robust testing strategy rather than optimizing for a number that can hit 100% while critical bugs slip through. A quick but eye-opening read for anyone serious about software quality.</p> <h2> Comparison </h2> <div class="table-wrapper-paragraph"><table> <thead> <tr> <th></th> <th>Code Coverage</th> <th>Test Coverage</th> </tr> </thead> <tbody> <tr> <td><strong>Question</strong></td> <td>Did we execute the code?</td> <td>Did we test all features?</td> </tr> <tr> <td><strong>Type</strong></td> <td>Quantitative (%)</td> <td>Qualitative (requirements)</td> </tr> <tr> <td><strong>Approach</strong></td> <td>White-box (code-aware)</td> <td>Black-box (input/output focused)</td> </tr> <tr> <td><strong>Purpose</strong></td> <td>Find untested code</td> <td>Verify requirements are met</td> </tr> </tbody> </table></div> <h2> Differences </h2> <p><strong>Code Coverage</strong> measures how much of your source code runs during tests. It's a number: 80%, 90%, etc.</p> <p><strong>Test Coverage</strong> measures how well your tests cover actual features and user scenarios. It's about completeness of requirements, not lines of code.</p> <h2> Example </h2> <p>You can have <strong>100% code coverage</strong> (every line executed) but still miss bugs. Why? Because you didn't test what users actually need to do—like "user can log in" - which is low test coverage.</p> <p>Conversely, good test coverage doesn't guarantee every code path was touched.</p> <h2> Bottom Line </h2> <p>Both metrics work together:</p> <ul> <li> <strong>Code Coverage</strong> = safety net (did we run it?)</li> <li> <strong>Test Coverage</strong> = quality net (does it work?)</li> </ul> beginners codequality programming testing