If you’re serious about making cocktails, you’ll need one of these: A Graduated Shot Glass. You can’t make truly great cocktails without one.

A graduated shot glass is essentially a measuring cup, but for booze. A good one will have measurements for several different kinds of measurements including ounces, tablespoons, teaspoons, and milliliters (in case you are feeling metric).

Now, It would be downright silly to suggest that the art of mixing cocktails requires exact measurements. No cocktail is going to suffer if you were supposed to add 2 oz. of gin, but only added 1.96 oz of gin. Unless you weren’t supposed to add gin, in which case: what were you thinking?

It’s All About Ratios

No, what a truly great cocktail requires is exact ratios. I’m sure you’ve heard people ask for a drink in parts or measures. A dry martini for instance is 5 parts gin and 1 part dry vermouth. Getting these ratios right is what elevates a cocktail to the sublime. Recipes with exact measurements are great for starting out, but you’ll soon find that you’re going to want to make smaller or larger amounts of these drinks or you’ll find you only have so much of one ingredient left. Knowing the right ratio for every drink means you’ll be good to go no matter what twists of lemon life throws at you.

All that being said, there is no easier and more effective way to get these ratios correct than using a graduated shot glass. Whether you actually are just following along with a recipe for the first time or are trying to do the math to figure out the ratios for a complicated drink, the graduated shot glass is the only tool you need to consistently make amazing drinks.

Uncool, But Effective

Now, I know the graduated shot glass is tremendously unsexy compared to other bar measurement tools like the jigger and the speed pourer, but let’s take a look at them:

The Jigger: OK for “Fast & Loose”

A jigger is both a measurement and a tool. In measurements 1 jigger equals 1.5 ounces and is based on the size of a standard shot glass. The tool is two metal cups connected together, one being smaller than the other. Standard jiggers usually come in two sizes: 1 jigger and ½ jigger and 1 oz. and ½ oz. Now, jiggers are fine for a lot of things, but you’ll soon find that far too many drinks require measures in thirds and quarters of a measure and trying to do that math with a jigger will make you go cross eyed.

The Speed Pourer: Inexact & Expensive

The speed pourer is the spout you see on the top of bottles at bars. These allow you to eyeball drinks more accurately and look like a professional in front of your friends. Using a speed pourer, every second you are pouring is about a half ounce. This ends up with the same problem as the jigger in terms of ridiculous math–how do you count ? of 2 seconds? Plus, depending on the size of your bar, you’re going to have to buy a lot of them, which can get expensive depending on quality.

The Graduated Shot Glass Makes Better Cocktails

Now, I know that part of the reason you set up your home bar was to look cool, sexy, and sophisticated in front of your guests and this tiny measuring cup makes you look like you are baking a tiny cake. However, once your guests taste their cocktails, they’ll forget it entirely and think you are the coolest, sexiest, and most sophisticated person they know. And not just because they are now blotto.