XG or xG may refer to: Organizations XG Technology, a wireless communications company SunExpress Deutschland (IATA code XG, 2011-2020), a German leisure airline headquartered in Frankfurt, Germany Clickair (IATA code XG, 2006-2009), a former low-cost airline based in Spain Science and technology Xg antigen system, a red blood cell surface antigen system DARPA XG, a DARPA communication program Hyundai XG, a Hyundai car model Yamaha XG, a Yamaha extension to the General MIDI standard Other uses XG (group), a Japanese girl group Extreme-G, a video game Expected goals (xG), a performance metric used to evaluate football team and player performance