Bottles of liquor come in many different sizes. The smaller range of sizes are typically rectangular and contain less than .5 liters. Larger cylindrical bottles (which I assume the question is referring to), usually contain .75; 1; and 1.75 liters.
It depends on the size. A regular whiskey bottle is 1/5 of a gallon, or 750 milliliters. A half-gallon bottle is 3.78 liters, or a pint is 473 milliliters.
Depending on the bottle, it can be between .375 liters for a mickey all the way up to 1.75 liters in a handle. The medium size bottle is generally 750 mililiters, or .75 of a liter.
