In the world of online gaming, lag can be the ultimate buzzkill. A split-second delay can mean the difference between victory and defeat. But what makes a game "lag-free"? It comes down to optimized servers, low-latency netcode, and lightweight game design. While no online game is entirely immune to lag, some titles stand out for their smooth performance, even under less-than-ideal network conditions. Below, we explore what makes a game lag-free and highlight a top contender for the most lag-free online game in 2025.