Weight converter

Convert between kilograms, pounds, ounces, grams and stones — useful for body weight, shipping and recipes.

How this calculator works

Weight conversions look simple but the units are not equally spaced: there are 16 ounces in a pound, 14 pounds in a stone, 1,000 grams in a kilogram, and a kilogram is 2.20462 pounds. The calculator converts everything to kilograms first, then out to each unit, which avoids cascading rounding errors.

Be aware of one terminology trap: in everyday use “weight” means mass, and the conversion factors above are for mass. Strictly, the pound-force is a unit of force measured in poundals, but scales report pounds as mass, so the everyday conversion is fine. Stones are still common in the UK and Ireland for body weight; the US and most of the world use pounds or kilograms. For anything regulated — medication doses, aircraft loading, freight — use the exact figure from the governing standard rather than a rounded conversion.

The formula

Convert to kilograms, then to the target unit:

So 70 kg = 154.324 lb = 11.023 st = 2,469.178 oz = 70,000 g.

Worked example

Converting 70 Kilograms gives 154.324 lb in pounds and 11.023 st in stones — 2,469.177 oz if you need ounces, or 70,000.000 g on a metric kitchen scale.

Common mistakes

• Mixing pounds and ounces. A weight of 10 lb 8 oz is 10.5 lb, not 10.8 lb. Convert the ounces first.
• Using 2.2 instead of 2.20462. The shortcut is fine for a rough check but drifts by about 0.2% — noticeable over large shipments.
• Confusing mass and force. Strict physics uses the pound-force for force and the pound for mass; household scales measure mass.