caffeine how much in green tea
Caffeine in Tea / March 16th, 2010. Naturally decaffeinated green tea contains about 2 milligrams of caffeine per cuppa. An average cup of green tea contains approximately 20-30 milligrams of caffeine depending upon the length of infusion. The longer the infusion time, the more caffeine in the cuppa. You may wonder why a decaffeinated tea would have any caffeine in it at all, but most do.