Liver math is the calculation(s) you make throughout the night to help determine if you are sober enough to drive home.

Alcohol is processed by the body at a determined rate (generally one beer/shot/wine glass an hour), and you can save yourself a night in the drunk tank and some legal fees by adhering to liver math.

Liver math or cab fare. Either is a wise choice. Disregard at your own peril.
Friend #1: "My ex just showed up here with her new bf. I'm leaving as soon as the liver math allows it."

Friend #2: "No way! You're my ride! Let's get fucked up and take a cab when the bar closes. I'll drive you to your car tomorrow."

Friend #1: "Good call. Screw that bitch, anyway."
by mrbean34 March 10, 2014
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