Caffeine is the natural stimulant every tea from Camellia sinensis carries, in different amounts, and it’s one of the few tea traits that isn’t decided by oxidation alone.
As a rough rule, black tea runs highest, followed by oolong, then green tea, then white tea. But that’s a starting point, not a formula. The plant’s variety, how old the leaf is when it’s picked, and how long and how hot it’s steeped all move the number too, sometimes more than the category itself does. A long, hot steep of a low-caffeine white tea can end up carrying more caffeine than a quick, cool steep of a black tea.
Not the whole story on its own
Caffeine rarely acts alone in tea the way it does in coffee. Theanine, an amino acid tea is unusually rich in, tends to soften caffeine’s edge, which is part of why tea’s energy tends to feel steadier and less jittery than a straight caffeine hit. Herbal teas sit outside this whole conversation, since they’re not made from the tea plant at all and are naturally caffeine-free rather than decaffeinated.
If you’re trying to manage caffeine deliberately, steep time and temperature matter as much as which category you reach for. A shorter, cooler steep pulls less caffeine out of the leaf regardless of type, which is worth knowing before assuming a tea’s category alone tells you what you’re getting.
