More than a latte, because of the chocolate
Starbucks lists 90 mg of caffeine for a Short Caffè Mocha, 95 mg for a Tall, 175 mg for a Grande, and 185 mg for a Venti. That is a little more than the same sizes of Starbucks’ Caffè Latte (75 mg Short/Tall, 150 mg Grande/Venti), even though both drinks use the same number of espresso shots. The difference is the mocha sauce: chocolate carries a small amount of caffeine of its own, on top of the espresso.
Chocolate adds up
That extra 20 to 35 mg is roughly what a serving of hot chocolate carries on its own, which is a useful way to picture it: a mocha is approximately a latte plus a portion of hot chocolate’s caffeine, combined. Starbucks’ White Chocolate Mocha breaks that pattern, since white chocolate carries no caffeine and that drink matches the latte’s numbers exactly.
The extra caffeine is small enough in absolute terms that it rarely changes how a mocha fits into a day compared to a latte, but it’s a real difference worth knowing if you’re counting milligrams closely rather than roughly matching drinks by size.
Where it fits in a day
At 175 mg, a Grande mocha sits under the 200 mg single dose EFSA assessed as safe for healthy adults; the 185 mg Venti does too, barely. Two Grandes, 350 mg, come close to the 400 mg daily figure the FDA cites for healthy adults. In pregnancy, where ACOG uses a 200 mg daily ceiling, a Grande alone is close to the whole day’s allowance.