Jiggers are typically used when measuring liquids for cocktails. They feature two conjoining cups that have different measurements. The larger side of the jigger has a volume of one and a half ounces, which is 1 shot here in the US. The smaller side holds 3/4 of an ounce. A shot glass is 1.5 ounces. If you don't have a shot glass or a jigger, you can use measuring spoons. 1.5 ounce equals 3 tablespoons. 3/4 of an ounce is 1.5 tablespoons.