Grape flavor with other natural flavors. Zero calorie. Zero sugar. 240 mg caffeine per can. B-vitamins. Taurine. Caffeine. Contains no juice. In Each Serving: taurine (100 mg), caffeine (120 mg), glucuronolactone (50 mg), inositol (25 mg). Total caffeine from all sources: 240 mg per can. www.rockstarenergy.com. Zero calorie per can.