oz

What is a Ounce?

The ounce is a small mass unit used in imperial and United States customary systems. One avoirdupois ounce equals 28.349523125 grams.

The ounce is a small mass unit used in imperial and United States customary systems. One avoirdupois ounce equals 28.349523125 grams.

Different ounce definitions existed historically, but the modern avoirdupois ounce is standardized through its 1/16 relationship with the pound.

Measurement system: Imperial and US customary systems. SI equivalent: 1 oz = 28.349523125 g.

Ounce facts

Unit name
Ounce
Symbol
oz
Category
Mass
Measurement system
Imperial and US customary systems
SI equivalent
1 oz = 28.349523125 g
Common uses
Packaging, food products and lightweight trade quantities

Definition of the ounce

The ounce is a small mass unit used in imperial and United States customary systems. One avoirdupois ounce equals 28.349523125 grams.

Measurement system and SI relationship

Imperial and US customary systems

SI equivalent: 1 oz = 28.349523125 g

History of the ounce

Different ounce definitions existed historically, but the modern avoirdupois ounce is standardized through its 1/16 relationship with the pound.

Where is the ounce used?

Packaging, food products and lightweight trade quantities

Ounce conversion tools

Other languages

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