Earl Grey is a black tea flavored with bergamot oil. Bergamot is a small citrus fruit from the Mediterranean. The caffeine in Earl Grey tea will be the same as other black teas. There has been debate...
I am pretty sure it depends on the tea. I'm not entirely sure, but it depends on the types like green or black. Also, the amount that you use. generally one bag of green tea has about 30mg caffeine