What is the caffeine content in green tea?

There is caffeine in green tea, this is because it contains the same plant that black tea uses; Camellia sinensis. However, the leaf of the plant is processed slightly differently for Green tea. The caffeine level in green tea tends to be lower at about 14mg to 37 mg per 250 ml compared to black tea at 25 – 110mg, and coffee at about 140mg per cup. However there are variables that will change the caffeine content such as how long you keep the tea bag in the cup.