From the FAQ [0]:<p>"How is a user's karma calculated?<p>Roughly, the number of upvotes on their posts minus the number of downvotes. These don't match up exactly. Some votes are dropped by anti-abuse software."<p>[0] <a href="https://news.ycombinator.com/newsfaq.html" rel="nofollow">https://news.ycombinator.com/newsfaq.html</a>