Troy Weight

An avoirdupois ounce is a unit of weight in the avoirdupois system, equal to one sixteenth of an avoirdupois pound.

As an exact measurement, an avoirdupois ounce is defined as 28.349523125 grams. For most practical purposes, this requires rounding to just two decimal places.

Here in the USA we often use the avoirdupois ounce for everyday weighing. Every time you step on the scale at home, or weight food found in the grocery, you use the avoirdupois ounce weight system. There are 16 avoirdupois ounces in a pound. 1 avoirdupois ounce = 437.5 grains, or 28.35 grams. 1 avoirdupois pound contains 16 (avoirdupois) ounces. This makes an Avoirdupois pound equal to about 453.6 grams, or the equivalent of 14.583 "troy ounces".

I personally use the pound avoirdupois.

There are 16 ounces in an avoirdupois pound.One avoirdupois pound is equal to a regular pound.