Cocktail Measurement Chart
Cocktail recipes are written in ounces, millilitres, parts, dashes and barspoons depending on where and when they were published, and mixing systems mid-recipe is how a balanced drink turns into an unbalanced one. This chart converts between all of them and lists the standard ratios behind the classic drink families.
Volume conversions
1 fluid ounce = 30ml = 2 tablespoons.
1/2 oz = 15ml, 3/4 oz = 22ml, 1 1/2 oz = 45ml, 2 oz = 60ml.
1 barspoon = roughly 5ml = 1 teaspoon.
1 dash (from a bitters bottle) = roughly 0.8-1ml, though this varies by bottle and by how hard you shake it.
1 pony = 1 oz / 30ml, 1 jigger = 1.5 oz / 45ml in traditional American bar usage, which is why 'jigger' means both the tool and a specific volume.
Standard jigger sizes
The most common double-sided jigger is 1 oz on one side and 1.5 oz / 2 oz on the other. Many also have interior lines marking 1/2, 3/4, and 1 1/4 oz.
Japanese-style jiggers are taller and narrower, which makes them more accurate at small volumes because the same volume error corresponds to a larger height difference. They typically come in 1 oz / 2 oz or 30ml / 45ml pairs.
Buy a jigger marked in the unit system your recipes use, and check that interior graduation lines exist for the in-between measures. A jigger with only the two end volumes forces awkward eyeballing for 3/4 oz, which appears constantly in sour recipes.
Working in parts
Recipes given in parts (2 parts spirit, 1 part citrus, 1 part syrup) are ratio recipes, meaning a part can be any unit as long as you use the same one throughout. That is what makes them convenient for batching: multiply every part by the same number.
The most common cocktail ratios are worth knowing directly. The sour: 2 parts spirit, 1 part citrus, 3/4 part sweetener. Equal parts: 1:1:1, as in the Negroni and the Last Word. Old Fashioned style: 2 oz spirit, 1 barspoon sugar or syrup, 2 dashes bitters. Highball: 1 part spirit to 3 parts mixer.
Batching for a group
To batch a cocktail, multiply every ingredient by the number of servings, then add water equal to roughly 20-25 percent of the total volume to replace the dilution that shaking or stirring would normally provide.
Batch only the shelf-stable components (spirits, liqueurs, bitters, syrups) ahead of time. Fresh citrus juice loses its brightness within about a day, so add it within a few hours of serving rather than the night before.