Pounds to ounces (lb to oz)

One pound is exactly 16 ounces. That ratio belongs to the customary system itself and is much older than any link to metric: the 1959 international yard and pound agreement later fixed the yard and the pound against the meter and the kilogram, but it left the ratios between customary units (feet to the yard, ounces to the pound, cups to the gallon) exactly as they were.

Worked through: 2 lb x 16 = 32 oz.

Going the other way, one ounce is 0.0625 pounds.

To convert without a calculator, multiply by 16. Rounding that to 16 is within 0% for most purposes.

Birth weights, boxing, postage and cooking. Sixteen ounces to the pound, so the decimal part of a pound figure times 16 gives the ounces: 7.5 lb is 7 lb 8 oz, not 7 lb 5 oz, which is the error people make reading it straight off.

Precision is worth matching to the input. A measurement given as 0.5 lb carries one or two significant figures, and reporting its conversion to six implies a precision the original never had.