How much caffeine is in your morning cup

Not all black teas hit the same. Here is what determines how much caffeine ends up in your morning cup.

A standard 240ml cup of English Breakfast carries roughly 40 to 70 milligrams of caffeine, depending on the leaf and the brew. For comparison, a single shot of espresso carries about 60 to 70mg, and a brewed coffee 95 to 165mg.

Three things drive how much caffeine you actually get in the cup. The first is the variety of the tea plant. Assam plants tend to produce more caffeine than Chinese small-leaf varietals. The second is brew time. Longer steeps extract more caffeine, though the rate of extraction slows after about three minutes. The third is water temperature, which matters less than the first two but still measurably.

If you want the caffeine without the bitterness, brew at the standard temperature but pull the leaves at three minutes. If you want a strong tea without much caffeine, drink white tea brewed long. White teas typically carry the least caffeine of any true tea.