Ounce oz
About the Ounce
The avoirdupois ounce is one sixteenth of a pound, exactly 28.349523125 grams. It is distinct from the troy ounce of 31.1034768 g used for precious metals, and from the fluid ounce, which measures volume. The word comes from the Latin uncia, a twelfth part.
Related Units
Pound
lb0.45359237 kg (exact)
The avoirdupois pound is defined as exactly 0.45359237 kilograms. The figure was chosen in the 1959 agreement as a...
Grain
gr64.79891 mg (exact)
The grain is exactly 64.79891 milligrams and is the one unit shared by the avoirdupois, troy and apothecaries' systems...
Kilogram
kgBase unit; h = 6.62607015 × 10⁻³⁴ J·s exactly
The kilogram is defined by fixing the Planck constant at exactly 6.62607015 × 10⁻³⁴ joule-seconds. Until 20 May 2019 it...
Tonne
t1 t = 1000 kg (exact)
The tonne, or metric ton, is one thousand kilograms, equal to one megagram. It lies between the US short ton of...