Body Weight Converter

Convert your weight between kilograms, pounds, and stones — the quick, everyday converter for fitness, health, and travel.

Body Weight

kg, lb, stone — bodyweight quick-convert

From

Result

2.204623

1 kg = 2.20462262 lb

Popular conversions

What Is a Body Weight Converter?

A body weight converter translates a person's weight between the three everyday systems — kilograms (metric, used in most of the world), pounds (US), and stones and pounds (UK and Ireland). It's a focused, simplified version of a general mass converter, tuned to the units people actually use for body weight, so you can read a scale, a fitness app, or a medical chart in whatever system is familiar.

This converter routes through the kilogram using the exact pound definition (1 lb = 0.45359237 kg). The stone, still common for body weight in Britain and Ireland, is 14 pounds (6.35 kg). Whether you're following a fitness plan, filling in a health form abroad, or comparing notes across countries, it gives the equivalent at a glance.

This is one category of the full Unit Converter — pair it with our percentage calculator or scientific calculator for related everyday maths.

How Body Weight Conversion Works

Everything routes through the kilogram

Each unit has a fixed kilogram value. The converter normalises to kilograms, then projects to pounds and stones.

The pound is exactly defined

1 lb = 0.45359237 kg, so kg ↔ lb conversions are exact. Multiply kg by 2.20462 for pounds.

Stones combine with pounds

1 stone = 14 lb = 6.35 kg. UK weights are given as 'stones and pounds', e.g. 11 st 4 lb, which this tool unpacks.

Body weight, not precise mass

Everyday weights are rounded; a scale reads to the nearest 0.1 kg or pound. The converter respects that everyday precision.

Core Body Weight Conversion Factors

Multiply to reach kilograms; divide to come back. The pound factor is exact.

kg → lb

× 2.20462

One kilogram is 2.20462 pounds. The everyday metric-to-US weight conversion.

Stone → kg

× 6.35029

One stone is 14 pounds = 6.35029 kg, used for body weight in the UK and Ireland.

Stone → lb

× 14

One stone is 14 pounds. UK weights combine stones and remaining pounds.

How to Use the Body Weight Converter

1
Enter the weight
Type the body weight you want to convert — your own, a target, or a figure from a chart.
2
Choose the 'from' unit
Pick kilograms, pounds, or stones as your starting unit.
3
Choose the 'to' unit
Select the target unit, or swap the two to reverse direction.
4
Read every unit at once
The all-units view shows the weight in kg, pounds, and stones together — useful when forms or apps differ.

Key Body Weight Concepts

Kilogram

The metric body-weight unit used in most of the world and in medicine. The SI base unit of mass, on which dosing and BMI are based.

Pound

The US everyday weight unit, exactly 0.45359237 kg. Scales and fitness apps in the US report pounds.

Stone

A UK and Irish unit of 14 pounds (6.35 kg). Body weight there is given as stones and pounds — e.g. 12 st 7 lb.

Weight vs BMI

Body weight alone doesn't indicate health; BMI combines weight and height. Convert weight first, then assess with the right tool.

Real-World Body Weight Conversions

⚖️

Reading a scale abroad

A scale showing 70 kg is 154 lb or 11 st 0 lb. Travellers convert to the units they know.

🏋️

Fitness tracking

A goal of losing 5 kg is 11 lb. Fitness apps switch between kg and pounds by region and preference.

🩺

Medical forms

A clinic abroad records weight in kilograms; a US form wants pounds. Converting fills either correctly.

🇬🇧

UK body weight

A weight of 80 kg is 12 st 8 lb. Britain and Ireland still use stones and pounds in everyday speech.

✈️

Travel and sport

Weight categories in sport (boxing, rowing) may use kg or pounds. Athletes convert to make a class.

📉

Tracking progress

Logging a drop from 90 kg to 84 kg (198 to 185 lb) lets you track in whichever unit motivates you.

Best Practices for Body Weight Conversion

✓Use the exact pound factor. 1 lb = 0.45359237 kg makes kg↔lb conversions exact. The rough '2.2' is fine for a mental estimate but slightly off for precise tracking.
✓Unpack stones and pounds. UK weights combine the two (e.g. 11 st 4 lb = 71.7 kg). Convert the whole figure, not just the stones.
✓Keep everyday precision. Scales read to ~0.1 kg or 0.2 lb. Reporting body weight to many decimals implies accuracy a bathroom scale doesn't have.
✓Convert weight before BMI. BMI needs weight in kilograms and height in metres. Convert pounds and stones to kg first, then compute BMI separately.
✓Match the unit to the context. Medicine and most of the world use kg; the US uses pounds; the UK uses stones. Convert to whatever the form or app expects.

Common Body Weight Conversion Mistakes

Forgetting the pounds in stones

Reading '11 st 4 lb' as just 11 stone drops 4 pounds (1.8 kg). UK weights must include the leftover pounds.

Using 2.2 for precise tracking

The exact factor is 2.20462 lb/kg. The rounded 2.2 is ~0.2% low — fine for estimates, slightly off for careful logging.

Confusing weight with BMI

Body weight alone isn't a health measure. BMI combines weight and height; convert weight first, then assess separately.

Mixing up the direction

kg is multiplied by 2.205 for pounds and divided to go back. Reversing it makes a 70 kg person appear to weigh 32 lb.

Why Body Weight Conversion Matters

Body weight is one of the most frequently converted numbers in everyday life: the world uses kilograms, the US uses pounds, and Britain and Ireland use stones, so a single weight wears three different labels. Fitness apps, medical forms, scales, and sport weight classes all assume one system, and converting lets you read and record your weight wherever you are.

While body weight alone isn't a measure of health — BMI and body composition matter more — getting the unit right is the starting point for tracking progress, completing medical paperwork, and comparing figures across countries. A focused converter that routes through the kilogram with the exact pound definition makes that quick and reliable.

Built for anyone tracking fitness, filling in health forms, or travelling — converting body weight between kilograms, pounds, and stones.

Linear unit factors follow the BIPM SI brochure, the NIST Guide to the SI, and ISO 80000. Currency rates load live from open.er-api.com; crypto prices from CoinGecko. See our methodology and editorial policy. Educational only — not certified for regulated trading, settlement, medical, or aerospace use.

Body Weight Converter FAQs

Multiply kilograms by 2.20462 to get pounds. So 70 kg is 154.3 lb, and 80 kg is 176.4 lb. To go the other way, multiply pounds by 0.453592 to get kilograms. The pound is defined as exactly 0.45359237 kg, so the conversion is exact — the rounded '2.2' factor is close but slightly low.

One stone equals 14 pounds, or about 6.35 kilograms. Body weight in the UK and Ireland is given in stones and pounds — for example, 11 st 4 lb means 11 stones plus 4 pounds, which is 158 lb or about 71.7 kg.

First convert kilograms to pounds (multiply by 2.20462), then divide by 14 to get whole stones, with the remainder as pounds. For example, 80 kg = 176.4 lb = 12 stones (168 lb) and 8.4 pounds, written as about 12 st 8 lb.

No. Body weight is just your mass; BMI (body mass index) combines weight and height to give a single figure (weight in kg ÷ height in m²) used as a rough health screen. Convert your weight to kilograms first, then use a BMI calculator — weight alone doesn't account for height or body composition.

The stone is a traditional British unit that has persisted for body weight in everyday use, even as the UK officially adopted the metric system. People there typically say their weight in stones and pounds (e.g. 'twelve and a half stone'), while medical settings increasingly use kilograms.

It uses the exact pound definition (1 lb = 0.45359237 kg) and the exact stone (14 lb), routing every conversion through the kilogram at full precision, so the result is exact to your input precision. In practice, body-weight figures are limited by your scale's precision, usually about 0.1 kg or 0.2 lb.