Weight Conversion Chart

Kilograms are used by scales and medical records nearly everywhere. Pounds alone are the American convention. Stones and pounds is how weight is spoken in the UK and Ireland, and it is the format general converters handle worst, because they return a decimal number of stones that nobody uses.

A converter that says 11.02 stone has not finished the job. Multiply the decimal part by 14 to get the pounds: 0.02 × 14 is 0.3, so the answer is 11 stone 0.3 pounds, spoken as "eleven stone".

The same carry problem appears here as with feet and inches. A figure that rounds to 14 pounds must roll over into the next stone, so 89 kg is 14 st 0.2 lb rather than 13 st 14.2 lb.

For everyday use, rounding a body weight to the nearest pound is fine. Two places where it is not: weight-based drug dosing, which is calculated per kilogram and where a rounded stone figure can move the weight by several kilograms, and competitive sport, where weight classes are defined to a fraction.

Airline and freight limits are the other common trap, because a 23 kg allowance and a 50 lb allowance are not the same limit. 23 kg is 50.7 lb, so packing to one rule and being measured against the other puts you marginally over.