When Starbucks introduced its trenta cup last week to 14 states, the company entered a new market and cup size to compete with convenience store drinks. The Arizona Daily Wildcat wondered how the trenta, which is only offered for Starbucks iced coffee and iced teas, compares to convenience store fountain drinks in terms of price and calories.

In terms of calories, Starbucks offers a similar number of calories per fluid ounce compared with Pepsi and Coca-Cola, its two main competitors at the convenience store. But getting an iced coffee or iced tea from Starbucks, unsurprisingly, can cost anywhere from three to seven times more than a fountain drink. Regardless of where you slake your thirst, however, you’ll have to decide if that enormous drink is really worth the cost.

Cost calculations

(For convenience stores, figures are based on fountain drink prices.)

Circle K

$0.79 / 32 fl oz = $0.025 per fluid ounce

$0.79 / 44 fl oz = $0.018 per fluid ounce

7-Eleven

$0.79 / 32 fl oz = $0.025 per fluid ounce

$0.79 / 44 fl oz = $0.018 per fluid ounce

$1.49 / 64 fl oz = $0.023 per fluid ounce

Quik Mart

$1.29 / 44 fl oz = $0.029 per fluid ounce

$1.49 / 64 fl oz = $0.023 per fluid ounce

Valero

$0.99 / 32 fl oz = $0.031 per fluid ounce

$0.99 / 44 fl oz = $0.023 per fluid ounce

$1.49 / 60 fl oz = $0.025 per fluid ounce

Starbucks

Iced coffee (with or without milk) $3.45 / 31 fl oz = $0.111 per fluid ounce

Iced tea $2.75 / 31 fl oz = $0.089 per fluid ounce

Iced tea lemonade $3.75 / 31 fl oz = $0.121 per fluid ounce