Starbucks Doubleshot Energy drinks contain approximately 135 milligrams of caffeine per 15 fl oz can. This applies to all flavors such as Mocha, Vanilla, Hazelnut, and White Chocolate

. To break it down further:

• The caffeine content is about 9 mg per fl oz.
• This caffeine amount is higher than many regular coffee beverages but less than some other Starbucks offerings like the Doubleshot on Ice, which has about 225 mg caffeine

• The drink also includes additional energy ingredients like guarana, ginseng, taurine, and B vitamins, which contribute to its energizing effects

In summary, if you are drinking a standard 15-ounce can of Starbucks Doubleshot Energy, expect around 135 mg of caffeine per serving