A standard jigger of alcohol contains 1.5 ounces, according to BarsAndBartending.com. A jigger is a measuring device shaped like an hourglass. It is used for mixing drinks to ensure that the correct amount of each ingredient is poured.
There are also jiggers that offer a variety of measurements, from 1 ½ ounces on one side and 2 ounces on the other to 1 ounce on one side and ½ ounce on the other. Standard double jiggers range from 1 ounce and ½ ounce to 1 ½ ounces and ¾ ounce. A half-shot is known as a pony shot, according to BarsAndBartending.com.