If you want to learn more about the weight of smaller items, you can find items around your house that weigh an ounce. You may be surprised how many common items weigh an ounce. From food items to coins and so many other things, plenty of household items weigh roughly an ounce.

**Common Items That Weigh an Ounce**

If you want to see what items add up to an ounce, grab a postal scale or small kitchen scale. If you want to start with money, you'll find that 10 pennies or five quarters weigh an ounce. About 28 paper clips weigh about an ounce, and so does a pencil. One of the most common items that weigh an ounce is a slice of whole-grain bread. Other items that weigh this much include AA batteries, six sheets of writing paper, and a compact disc.

**History of Ounces**

The ounce became a unit of measurement in Great Britain in the Middle Ages. Measurements weren't always consistent, and the British changed how many ounces totaled a pound several times. By 1266, a pound was 12 ounces, but by 1304, a pound of medicine was 12 ounces while other items were weighed to a pound that equal 15 ounces. Not long after that, a pound became a standard 16 ounces. In case you've ever wondered why the abbreviation for ounces is "oz" instead of something that seemingly makes more sense, the abbreviation comes from the Italian word for ounce, "onza."

**Different Types of Ounces**

If the history of ounces and how varying numbers of ounces made up a pound at different times wasn't confusing enough, there are different types of ounces today. These types of ounces serve specific functions for measuring mass.

An avoirdupois ounce is the type of ounce we use to measure dry goods while a fluid ounce measures the volume of liquids. They're nearly identical in size, even though they correspond to different metric measurements. The other type of ounce is the troy ounce, which measures the mass of precious metals and is slightly larger than the other types of ounces.

**Other Measurements of Mass and Volume**

Other ways than ounces that people measure the mass of solid items include pounds and tons in the standard system of measurement. The metric system measures mass using grams and their multiples, including kilograms.

Other measurements for liquids in the standard systems include cups, pints, quarts, and gallons. The metric system uses liters to measure the volume of liquids, including multiples and fractions of liters like milliliters and kiloliters.

**How Ounces Correspond to Other Measurements**

Ounces correspond differently to the standard system of measurement that we use in the United States than to the metric system that many other countries use. An avoirdupois ounce is roughly 28.349 grams, while a fluid ounce is approximately 29.574 milliliters. A troy ounce is around 31.103 grams. A fluid ounce is 0.0625 of a pint, 0.03125 of a quart, or 0.007812 of a gallon while an avoirdupois ounce is 0.0625 of a pound.