The term's origin is a fascinating mix of translation and phonetic evolution. It started in the Chinese gaming community for “World of Warcraft,” where a high-level material was called “Khorium,” which was translated as 氪金 (kèjīn). Players needed a lot of it, so it became associated with great expense. Later, this term blended with a Japanese gaming term, 課金 (kakin), which means “to charge a fee.” The result is 氪金 (kèjīn), a perfect slang word that sounds like “levying money” but with a cool, sci-fi “Krypton” flair, implying something powerful and almost otherworldly that you have to pay for.
In China, the dominant model for mobile and online games is “Free-to-Play” (F2P). Games are free to download, but their entire business model revolves around encouraging players to 氪金. This has created a distinct gaming culture with its own vocabulary and social dynamics. The core cultural dynamic is the trade-off between time and money. This is perfectly captured by two opposing terms:
This creates a spectrum of players, from the 零氪 (líng kè) (zero-spending F2P player) to the 微氪 (wēi kè) (light spender) to the 重氪 (zhòng kè) (heavy spender, or “whale”). Being a heavy spender is often associated with the term 土豪 (tǔháo), or “nouveau riche,” and can be a source of both admiration and envy within the game community. Compared to the Western concept of “microtransactions,” 氪金 is a much more integrated and versatile slang term. While “microtransaction” is a formal, industry term, 氪金 is a word used colloquially by millions of players every day. It's a verb (“I need to 氪金”), a noun (“This game is all about 氪金”), and an adjective (“This is a very 氪金 game”).
氪金 is used almost exclusively in the context of video games and virtual goods. It's highly informal and common among young people on social media, in chat groups, and in daily conversation about hobbies.