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How Many Fluid Ounces in a Cup?

How many fluid ounces are in a cup? It seems like a straightforward question in cooking and baking.

But, the answer depends on where you live. Did you know liquid is not measured the same way worldwide?

Measuring Cup Photo

The United States has its own system of measurement. It’s different than the metric system and the British imperial system.

The United States Customary System (USCS or USC) developed from English units used by the British Empire before America became an independent country. But, then, in 1824, the British Empire overhauled its measurement system, instituting imperial units instead.

By the late 20th century, most of the countries from the British Empire switched to the metric system, which is based on decimals. But, some imperial units are still used in the United Kingdom, Canada and other nations that used to be part of the British Empire.

Measuring Cup Picture

The metric system is now used by almost all nations. In fact, the United States is the only industrialized country in the world that doesn’t use the metric system as its main system of measurement.

But the metric system doesn’t use ounces. It measures liquid in milliliters.

So, if you want to know how many fluid ounces are in a cup, we need to look at U.S. measurements and imperial units.

Measuring Cup Image

U.S. Fluid Ounces Per U.S. Cup

When using United States measurements, there are 8 fluid ounces in a cup.

Imperial Fluid Ounces Per Imperial Cup

There are 10 imperial fluid ounces in an imperial cup.

Measuring Cup Pic

U.S. Fluid Ounces Per Imperial Cup

There are 9.6 U.S. fluid ounces in an imperial cup. So, an imperial cup is bit larger than an American cup.

Imperial Fluid Ounces Per US Cup

There are 8.3 imperial fluid ounces in a U.S. cup.

Confused yet? You might want to head over to the cocktails section.