A Starbucks tall is 12 ounces; grande is 16; venti is 20 and
trenta is 31 ounces. To save a bit, you can order a “short.” A
Starbucks short is 8 ounces and is a member of the Starbucks
product offering. It is just not on the menu.
Incidentally, refills are free if you order with the Starbucks
app or fifty cents for regular coffee or tea (hot or iced).