Maybe they're being generous. Or it is supposed to be 32oz and they are skimping on their portions, like cans that contain 7.5oz instead of a round 8.

Apparently the venti coffee cup is 20oz but then they launched a large cold drink cup of 24oz which they also called venti and then a larger 31oz cup which they called trenta. I blame the marketing department.

Can confirm, the cold Venti is slightly bigger (most likely to account for ice).

So if I order my next iced chai without ice I will get more? :)

I...thought it was 30. It's labeled as 30.

Huh. The more you know.