Mass & Weight Converter

Worked example

1 kg ≈ 2.204622622 lb, because 1 lb is exactly 0.45359237 kg. A US ton is 2,000 lb, which is 907.18474 kg, while an Imperial ton is 2,240 lb, which is 1,016.0469088 kg. The two tons are different units.

How it works

Every unit converts through the kilogram using exact defined factors. The pound is exactly 0.45359237 kg (the 1959 international agreement), an ounce is one sixteenth of a pound, a stone is 14 pounds, a US (short) ton is 2,000 pounds and an Imperial (long) ton is 2,240 pounds. The word “ton” is never used on its own, because the two tons differ by 12%, and “ounce” here always means the avoirdupois ounce, not a fluid ounce. This converts mass, the everyday “weight” on a scale, not weight as a force in newtons. Enter zero or more: a mass cannot be negative.

A result written as a plain number is exact. A result starting with “≈” has been rounded to 10 significant figures, because its exact decimal never ends or is too long to read comfortably. When an exact value is long, its full digits are shown underneath. The calculation itself is never rounded: only the display is.