Depends on the kind of tea. Higher the oxidation level, the longer you steep it, and various ingredients can alter the caffeine level. Not 100% accurate, but i

Depends on the kind of tea. Higher the oxidation level, the longer you steep it, and various ingredients can alter the caffeine level. Not 100% accurate, but it goes something like: black → green → white → chamomile (which is naturally caffeine free if chamomile is the only ingredient) Green tea in many cases has nearly the same caffeine content as black tea though.