Convert Pounds to Ounces – Weight Converter

This converter uses the avoirdupois system, where 1 pound (lb) is defined as exactly 16 ounces (oz). This is the standard relationship used in food labeling, commercial weighing instruments, and most engineering handbooks.

Modern definitions tie the pound to the kilogram: 1 pound is defined as exactly 0.45359237 kilograms. The ounce is derived from the pound, so 1 ounce equals 1/16 of a pound. These definitions are maintained and disseminated by national metrology institutes such as NIST.

The converter applies a simple linear relationship: ounces = pounds × 16. Because the factor is exact in the avoirdupois system, no additional correction terms or approximations are required under normal conditions.

In practical use, any apparent rounding comes from how many decimal places you choose to display. For example, if you enter a value in pounds with several decimal places, the resulting ounces will be an exact mathematical multiple of 16, but may be rounded for display to keep the result readable.

The tool is intended for ordinary and professional applications that rely on the standard avoirdupois pound and ounce. It is not intended for troy weight (used in precious metals trading) or apothecaries' measures, which follow different historical relationships.

Example 1 – Simple whole-number conversion: If a recipe calls for 2 pounds of flour, multiply 2 by 16 to get 32 ounces. Enter 2 lb into the converter and you will see 32 oz.

Example 2 – Mixed or fractional pounds: If a shipping label lists 3.5 pounds, multiply 3.5 by 16 to get 56 ounces. Enter 3.5 lb and the converter returns 56 oz, which you can use for packaging specifications or rate tables.

Example 3 – Converting small weights: If an ingredient weighs 0.25 pounds, multiply 0.25 by 16 to get 4 ounces. This is useful when a kitchen scale shows pounds with decimals, but your recipe is written in ounces.

Example 4 – Back-checking an instrument: If a lab balance shows 1.875 pounds, converting to ounces gives 1.875 × 16 = 30 ounces. Comparing the converted value with expected tolerances can help you verify that the balance is reading consistently with other instruments.

This converter uses the exact relationship 1 pound (lb) = 16 ounces (oz) from the standard avoirdupois system tied to the international kilogram definition.

Because the conversion factor is exact, any uncertainty in your result mainly comes from the accuracy and calibration of your weighing instrument, not from the mathematics of the conversion itself.