What's a jigger?

A jigger is a small double-ended metal measuring cup used to portion spirits and modifiers in cocktails. The two ends are typically 1 oz and 0.5 oz (or 1.5 oz and 0.75 oz).

A jigger is the bartender's measuring cup. Most jiggers are hourglass-shaped with two different-sized cones — a larger one and a smaller one. Common sizes: 1 oz over 0.5 oz (a 'standard' jigger) or 1.5 oz over 0.75 oz (a 'big' jigger). Many modern jiggers have internal etched lines marking smaller measures (0.25 oz, 0.75 oz, etc.) so a single tool covers most pours. Why bother with a jigger at home: cocktails are recipes. A Daiquiri is 2 oz rum, 1 oz lime juice, 0.75 oz simple syrup — a 2:1:0.75 ratio. Pour those by eye and the drink can be way off; pour them with a jigger and the drink is identical every time. Professional bartenders use jiggers continuously even after 20 years behind the bar because the consistency matters more than the speed cost. The most useful starter jigger for home use is a Japanese-style 2 oz / 1 oz with internal etched 0.25 and 0.75 lines, available for under $15.