Reddit Course Part 4 — Q175–222

## Module 7 — Karma, scoring, and incentives ### How exactly is post karma calculated from upvotes and downvotes? Post karma is Reddit's way of quantifying the reception of the content you submit as links, images, text posts, or videos. At its most basic level, post karma increases when other users upvote your posts and decreases when they downvote them. However, the relationship is not a simple one-to-one exchange. Reddit has never publicly disclosed the exact formula its algorithm uses, but community research and observation over many years have revealed some consistent patterns about how the system behaves. The first and most important thing to understand is that karma is not simply upvotes minus downvotes. A post that receives 1,000 upvotes will not reward you with 1,000 karma points. The algorithm applies what appears to be a diminishing-returns function, meaning each additional upvote contributes progressively less karma as a post accumulates more votes. The effect becomes especially noticeable on posts that go viral. Users have reported receiving viral posts with tens of thousands of upvotes only to see their post karma increase by a few thousand points, not the full vote count. One documented case involved a post at roughly 40,000 upvotes yielding just over 4,000 karma, and there are reports of posts crossing 200,000 upvotes where karma stopped increasing entirely — appearing to plateau around 9,000 points of gain from a single post. The speed of vote accumulation also appears to matter. Posts that receive a surge of upvotes early tend to generate more karma per vote than posts that earn the same total over a longer period. This likely reflects how Reddit's ranking algorithms favor momentum, and karma calculation seems to be intertwined with the same timing signals. Early votes may carry heavier individual weight in the karma calculation than votes that arrive after a post has already become popular. Downvotes reduce karma at a proportional rate, though Reddit does not specify whether the penalty is symmetrical with the gain. Because of vote fuzzing — a deliberate obfuscation of displayed vote counts — you cannot observe the true net score at any given moment, which makes independent testing of the formula extremely difficult. Finally, it is worth noting that your own initial upvote on a post — which every post starts with — does not count toward your karma. You are not rewarded for voting on your own content. The karma you see in your profile represents the cumulative, algorithmically-processed reception of your posts by others over the lifetime of your account.