Stone to kilograms
Multiply stone by 6.3503 to get kilograms.
12 st = 76.2035 kg
How to convert stone to kilograms
The kilogram is the SI base unit of mass, fixed since 2019 by defining the Planck constant as exactly 6.62607015×10⁻³⁴ J·s. The stone is exactly 14 pounds — the imperial unit defined in Schedule 1 of the UK Weights and Measures Act 1985, so 1 st = 6.35029318 kg exactly.
Worked example — 12 st: 12 × 6.3503 = 76.2035 kg.
Stone to kilograms table
| Stone | Kilograms |
|---|---|
| 1 st | 6.3503 kg |
| 8 st | 50.8023 kg |
| 10 st | 63.5029 kg |
| 11 st | 69.8532 kg |
| 12 st | 76.2035 kg |
| 13 st | 82.5538 kg |
| 14 st | 88.9041 kg |
| 15 st | 95.2544 kg |
| 20 st | 127.0059 kg |
Reverse and related
About stone and kilograms
Stone (st)
1 st = 6.3503 kgDefinition. Exactly 14 pounds — the imperial unit defined in Schedule 1 of the UK Weights and Measures Act 1985, so 1 st = 6.35029318 kg exactly
History and origin
The stone was a trading weight that varied by commodity and region across medieval Europe before Britain fixed it at 14 pounds. It is defined in Schedule 1 of the UK Weights and Measures Act 1985.
Current use
The stone is still the usual way to give body weight in the United Kingdom and Ireland, where a person might be eleven stone four, but it is little used elsewhere.
Source: Weights and Measures Act 1985 (UK), Schedule 1, Part VI
Kilogram (kg)
1 kg = 0.157473 stDefinition. The SI base unit of mass, fixed since 2019 by defining the Planck constant as exactly 6.62607015×10⁻³⁴ J·s
History and origin
The kilogram began in 1795 as the mass of one litre of water at the melting point of ice, and from 1889 was embodied in a platinum-iridium cylinder kept near Paris, the International Prototype Kilogram. In 2019 the SI retired that physical artefact and redefined the unit through a fixed value of the Planck constant, leaving its size unchanged.
Current use
It is the base unit of mass almost everywhere on Earth. The main everyday exception is the United States, where people weigh in pounds even though US science, medicine and industry work in kilograms.
Source: BIPM, The International System of Units (SI), 9th ed. (2019)
Where people use this
Stone: body weight in the UK and Ireland. Kilograms: body weight outside the US, groceries and produce, checked-luggage limits. 11 st is about 69.9 kg.
Every value is carried to full double precision; the display is rounded.
Sources: BIPM, The International System of Units (SI), 9th ed. (2019); Weights and Measures Act 1985 (UK), Schedule 1, Part VI.
Questions people ask
How many kg is 11 stone?
11 stone is about 69.9 kg (11 × 6.35029 = 69.85 kg). To convert stone to kg, multiply by 6.35.
How many kg are in a stone?
One stone is about 6.35 kilograms (exactly 6.35029 kg).
What is 12 stone in kg?
12 stone is about 76.2 kg, and 14 stone is about 88.9 kg.