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Multiple conversions
To convert from Stone (st) to Microgram (mcg), use the following formula:
Microgram (mcg)
= 14 × 453.59237 × 106× Stone (st)
= 6350293180× Stone (st)
With 453.59237 is the ratio between the base units Gram (g) and Pound (lb).
To convert from Stone (st) to Milligram (mg), use the following formula:
Milligram (mg)
= 14 × 453.59237 × 1000× Stone (st)
= 6350293.18× Stone (st)
With 453.59237 is the ratio between the base units Gram (g) and Pound (lb).
To convert from Stone (st) to Gram (g), use the following formula:
Gram (g)
= 14 × 453.59237× Stone (st)
= 6350.29318× Stone (st)
With 453.59237 is the ratio between the base units Gram (g) and Pound (lb).
To convert from Stone (st) to Kilogram (kg), use the following formula:
Kilogram (kg)
= 14 × 453.59237 × 11000× Stone (st)
= 6.35029318× Stone (st)
With 453.59237 is the ratio between the base units Gram (g) and Pound (lb).
To convert from Stone (st) to Metric Tonne (mt), use the following formula:
Metric Tonne (mt)
= 14 × 453.59237 × 1106× Stone (st)
= 0.00635029318× Stone (st)
With 453.59237 is the ratio between the base units Gram (g) and Pound (lb).
To convert from Stone (st) to Ounce (oz), use the following formula:
Ounce (oz)
= 14 × 16× Stone (st)
= 224× Stone (st)
To convert from Stone (st) to Pound (lb), use the following formula:
Pound (lb)
= 14× Stone (st)
To convert from Stone (st) to Ton (t), use the following formula:
Ton (t)
= 14 × 12000× Stone (st)
= 0.007× Stone (st)
The stone (st) is a unit of measurement equal to 14 pounds (lb).
It's part of the imperial system and is still commonly used in a few countries, especially for weighing people.
For use in international contexts or scientific applications, the stone is often converted to the metric system.
One stone is equal to exactly 6.35029318 kilograms (kg).
This precise conversion is used in international trade and science to ensure everyone is using the exact standard measurement.
Although it's an older unit, the stone remains the primary unit of measurement for body weight in the United Kingdom and Ireland.
It's common to hear someone state their weight as a combination of stone and pounds, like "12 stone 6 pounds."
The stone traces its origins back to the medieval English wool trade, where a "stone of wool" referred to a standard 14-pound measure used for buying and selling.
Stones for other goods could vary in weight—for example, a stone of glass was just 5 pounds—but over time, the 14-pound stone became the official legal standard.
The stone is almost never used on its own. Body weight in Britain and Ireland is quoted as stones and pounds, with the remainder written out rather than expressed as a decimal.
A person weighing 72 kg is "11 stone 4" — that is 11 st 4 lb, or 158 pounds — not "11.3 stone". Reading the decimal form as pounds is a common error: 11.3 st is 11 st 4.2 lb, close by coincidence, but 11.5 st means 11 st 7 lb, not 11 st 5 lb.
The conversions worth keeping to hand are:
The unit's survival is unusually specific. It was removed from British trade use by weights and measures legislation, so nothing is sold by the stone — shop scales read in kilograms and grams.
What survives is personal and conversational use: body weight, and by extension the weight of livestock and sporting figures such as boxing and horse-racing weights. Medical records in the UK are kept in kilograms, but patients are routinely told their weight in stones and pounds because that is the number they recognise.
Outside Britain and Ireland the unit is essentially unknown. The United States, despite sharing the pound, does not use the stone at all — American body weight is quoted in pounds alone, which is why a US figure of "158 lb" and a UK figure of "11 st 4" describe exactly the same person.