Caffeine Content in Teas

Caffeine content in teas
We all need a little bit of caffeine to get us through our day sometimes. Whether you need just a slight boost or a full on wake-up call, there is a tea for you out there.
Caffeine is one the components of tea and all types of tea (except for herbal) contain caffeine. However, the amount of caffeine varies according to type. In general, Green tea contains the least caffeine, Black tea the most, and Oolong falls somewhere in between.
  • A cup of Green tea (6 oz) contains 8 to 36 mg of caffeine.
  • A cup of Oolong tea contains 12 to 55 mg of caffeine.
  • A cup of Black tea ranges from 25 - 110 mg.
  • Coffee generally contains 150 - 200 mg of caffeine.
In the case of obese people, green tea is the safest choice.

Water temperature and steeping time can result in different caffeine amount released from tea.
Water temp. (°c) Caffeine Released (%)
93.3 90
87.7 87
82.2 83
65.5 57
   Percentage of caffeine released
   against water temperature (°c).
Steeping time (minutes) Caffeine Released (%)
1 38
2 48
4 72
6 90
    Percentage of caffeine released
    against steeping time (minutes).

Note: As beverages vary widely according to the way they are made, all figures provided herewith are approximate.