KG to Stone Conversion Guide: Kilograms to Stone & Pounds

In the UK, we commonly express body weight in stone and pounds, while medical professionals and fitness equipment often use kilograms. This guide helps you convert between these systems with ease.

The Conversion Formulas

Quick Reference: KG to Stone Chart

Detailed KG to Stone Conversion Table

How to Convert KG to Stone and Pounds

Stone to KG Conversion Chart

Pounds to Stone Quick Reference

Since 1 stone = 14 pounds, here's how pounds relate to stone:

Why the UK Uses Stone

The stone has been used in the British Isles for centuries, originally for weighing agricultural commodities. While the UK officially adopted the metric system in 1965, stone remains the most common way to express body weight in everyday conversation.

Where Different Units Are Used

• Stone and pounds: Everyday conversation, older scales, traditional contexts
• Kilograms: Medical settings, fitness equipment, scientific contexts
• Pounds only: US influence, some fitness apps

BMI Calculations with Stone and KG

Body Mass Index requires weight in kilograms:

Weight Loss Tracking

When tracking weight loss, it's helpful to understand both units:

Quick Mental Conversion Tips

Common Weight Benchmarks

Conclusion

Key conversion facts to remember:

• 1 stone = 6.35 kg = 14 pounds
• 10 stone = 63.5 kg = 140 pounds
• To convert kg to stone: divide by 6.35
• To convert stone to kg: multiply by 6.35
• For stone and pounds: get whole stone, then multiply decimal by 14 for pounds

Whether you're tracking fitness goals, understanding medical information, or just curious about your weight in different units, these conversions will help you navigate between the systems used in the UK.

NHS Weight Guidelines and the Stone

The NHS uses both kilograms and stone when communicating with patients about healthy weight ranges. GP surgeries across the United Kingdom typically weigh patients in kilograms using calibrated medical scales, but will often translate the reading into stone and pounds because that is what most British people understand intuitively. The NHS Healthy Weight Calculator, available on the nhs.uk website, accepts input in either stones and pounds or kilograms and provides BMI results alongside personalised guidance.

According to NHS guidelines, a healthy BMI falls between 18.5 and 24.9. For a person who is 5 feet 7 inches tall (170 cm), this translates to a healthy weight range of roughly 8 stone 3 pounds to 11 stone 2 pounds (52 kg to 71 kg). The NHS recommends that adults who are overweight aim to lose weight at a rate of 1 to 2 pounds (0.45 to 0.9 kg) per week, which equates to roughly one stone every 7 to 14 weeks. Weight management services commissioned by local authorities throughout England, Scotland, Wales, and Northern Ireland all use these dual-unit references to ensure patients can relate to the numbers being discussed.

Stone and Pound Breakdown Table

Because one stone equals exactly 14 pounds, it is useful to know how individual pounds translate within a stone. The table below shows the kilogram equivalent for each pound increment within a single stone, which is particularly helpful when reading bathroom scales that show fractional stone values.

History of the Stone Measurement

The stone as a unit of weight has roots stretching back to antiquity, but it was formalised in England during the medieval period. Historically, the stone varied in size depending on the commodity being weighed and the region. A stone of wool, for instance, was defined as 14 pounds by a royal charter of Edward III in 1340, while a stone of meat or fish could differ. The Weights and Measures Act of 1824 standardised the stone at exactly 14 avoirdupois pounds (6.35029 kilograms) across the United Kingdom.

Despite the UK's official adoption of the metric system under the Weights and Measures Act 1985, the stone was granted an exemption for use in personal weight descriptions. It remains widely used in everyday British and Irish life, though it is not recognised as a legal unit of measurement for trade. Countries such as Australia, Canada, and New Zealand, which once used the stone as part of the imperial system, have fully transitioned to kilograms. The stone is therefore something of a uniquely British and Irish cultural marker, one of the few imperial measurements that persists in daily conversation even among younger generations.

Frequently Asked Questions

Why do UK doctors weigh patients in kilograms but discuss weight in stones?

Medical equipment in the UK is calibrated in kilograms because drug dosages, anaesthetic calculations, and clinical guidelines are all based on metric units. However, most British patients think of their weight in stones and pounds because that is the system they grew up with. To bridge this gap, GPs and nurses will often convert the kilogram reading into stones and pounds during consultations. NHS weight management programmes, including the NHS Digital Weight Management Programme, provide guidance in both units to ensure accessibility for all patients.

Is the stone used anywhere outside the United Kingdom?

The Republic of Ireland also uses the stone informally for body weight, sharing the UK's cultural tradition. However, no other country actively uses the stone in daily life. Australia, Canada, South Africa, and New Zealand all abandoned the stone when they metricated during the twentieth century. In the United States, body weight is expressed in pounds only, without the stone subdivision. The stone is therefore largely a British and Irish convention, and its continued use is considered a distinctive feature of these nations' relationship with measurement systems.

How accurate does my kg-to-stone conversion need to be for health purposes?

For general health monitoring and weight tracking, rounding to the nearest pound is perfectly adequate. If you weigh 78.3 kg, converting this to 12 stone 5 pounds (rather than the precise figure of 12 stone 4.76 pounds) will not affect any health decisions. The NHS BMI calculator itself rounds to one decimal place. However, if you are calculating medication dosages or preparing for a medical procedure, always use the exact kilogram figure as provided by calibrated medical scales rather than a converted stone value.