How to Measure a Cocktail That Uses Parts

As you browse cocktail recipes, you will often find the measurements of ingredients listed in ounces, milliliters, dashes, and splashes. Those are very straightforward, but what happens when you come across a cocktail that uses the term "parts" instead?

Measuring parts is quite easy, and you simply need to do a little math to make a great drink. To do this, it's helpful to understand the standard measurements used in cocktails.

How to Measure Cocktail Ingredients

Most often, cocktail recipes use fluid measurements. In the United States, the imperial system is used, and each ingredient is given in ounces. Where the metric system is employed, ingredients are measured in milliliters. Both offer more precise measurements than tablespoons and cups. These volume measurements are also used for liquor bottles, mixers such as soda and syrup, glassware, and cocktail shakers.

Bartenders use a jigger—a dual-cup bar tool—to accurately measure cocktail ingredients. Jigger sizes vary, ranging from 1/4 ounce to 2 1/2 ounces, and, typically, the larger cup is twice the volume of the smaller cup. For instance, the most common jigger measures the standard 1 1/2-ounce shot, and the opposite end holds 3/4 ounce of liquid. Metric jiggers work the same way. Shot glasses are a good alternative, generally measuring either 1 ounce or 1 1/2 ounces (some hold 2 ounces).

Ounces and milliliters do not match up precisely. Technically, 1 1/2 ounces is equal to 44.3603 milliliters, but there's no need to be that specific. Instead, when converting a U.S. recipe to metric (or vice versa), it's good to know the standard shot measurements used by bartenders.

How to Measure Parts

Proportion is more important than precision, and that's one reason why some drink recipes are written in parts. "Parts" are imprecise measurement units: "1 part" is any equal part of the total volume. It could be 1 ounce for a single cocktail, 1 cup for a punch, or any other measurement. This also makes converting from imperial to metric easy.

Whenever you're faced with a recipe that uses parts, begin by determining your basic measurement—your "1 part"—then divide or multiply the other ingredients to maintain the ratio. For example, 1 part can be one full jigger: pour two jiggers for 2 parts, and one-half jigger for 1/2 part.

By knowing how much liquid (and ice) your glassware will hold, you can determine what your 1 part should be. For instance, a martini glass holds a smaller volume than a highball glass, so 1 part for a martini might be 1 ounce, while 2 ounces is a better fit for a highball.

Cocktail Recipe Examples

To put this theory into action, it's helpful to see how parts are used in real cocktail recipes. Some are very easy, while others require interpretation.

The Easiest Parts Conversion

In the majority of drink recipes, you can simply replace the word "parts" with "ounces" (or "milliliters"). Look for recipes that have 1 1/2 or 2 parts for the base liquor, then pour all of the ingredients with the measurements given.

The "Danny Ocean" cocktail is a perfect example:

• 1 1/2 parts reposado tequila
• 3/4 parts lemon juice
• 3/4 parts pink grapefruit juice
• 1/2 part agave nectar
• 1/4 part maraschino liqueur

To pour this cocktail, begin with 1 1/2 ounces tequila. Then pour 3/4 ounce of each juice, 1/2 ounce nectar, and 1/4 ounce maraschino.

A Simple Parts Example

The "pumpkin divine" cocktail is another simple recipe measured in parts. However, this one uses 1 part, so you need to determine what that 1 part equals.

• 1 part pear vodka
• 1 part pumpkin butter
• 1/2 part triple sec
• 1/2 part simple syrup

To make it very easy, pour one jigger (1 1/2 ounces) each of vodka and pumpkin butter, then one-half a jigger (3/4 ounce) each of triple sec and syrup. After shaking, you have a 5-ounce cocktail, the perfect size for a modern cocktail glass.

A Complex Parts Example

You may come across a drink like the "time for a change" cocktail on rare occasions. This one is rather complicated because the parts are precise but not standard:

• 2 1/2 parts bourbon
• 1/4 part triple sec
• 1/2 part fresh lemon juice
• 1/2 part blueberry juice
• 1/2 part lavender honey syrup

This is served in a cocktail glass, so it doesn't make sense to start with two and a half 1 1/2-ounce jiggers (or 3 3/4 ounces) of bourbon. The drink would be too large for the glass, and that's a lot of whiskey for a single cocktail (though you could make two drinks at once).

Instead, pour 2 ounces of bourbon, 1/3 ounce triple sec, and 3/4 ounce of each juice and the syrup. Again, you will have approximately a 5-ounce cocktail.

If you want to get technical, that triple sec pour would be 1/5 ounce and the juices and syrup 2/5 ounce each. The numbers are rounded off to standard pours because it's difficult to be that precise. It's also important to remember that any drink can (and should) be adjusted to your personal taste. 

Use Parts to Convert Drink Size

You can think in terms of parts to customize the size of any drink recipe. This is helpful when you want to increase or decrease a drink's volume without changing the ingredients' ratio.

For instance, if you want to transform the sea breeze into a martini, pour 1 part (2 ounces) cranberry juice, 1/2 part (1 ounce) vodka, and 3/4 part (1 1/2 ounce) grapefruit juice. The cocktail will taste the same as it does when served in a highball glass, but now you can shake it and serve it in a cocktail glass without ice for a fancier presentation.

Parts are also helpful when you want to make a punch out of a cocktail. For a large volume, this works best for drinks with a lot of juices and nonalcoholic mixers. However, you can also use parts to make a pitcher of martinis or mojitos for a few people.