Stones to Kilograms Converter
Convert between UK/Irish stones and metric kilograms with precision
Weight Converter
UK/Irish unit (1 stone = 14 pounds)
Metric unit (SI standard)
Conversion Formula
1 stone = 6.35029318 kilograms
Kilograms = Stones × 6.35029318
Since 1 stone = 14 pounds and 1 lb = 0.45359237 kg
Conversion Results
Quick Conversion Tables
Stones to Kilograms
| Stones | Kilograms |
|---|---|
| 1 st | 6.35 kg |
| 5 st | 31.75 kg |
| 8 st | 50.80 kg |
| 10 st | 63.50 kg |
| 12 st | 76.20 kg |
| 14 st | 88.90 kg |
| 15 st | 95.25 kg |
Kilograms to Stones
| Kilograms | Stones |
|---|---|
| 50 kg | 7.87 st |
| 60 kg | 9.45 st |
| 70 kg | 11.02 st |
| 80 kg | 12.60 st |
| 90 kg | 14.17 st |
| 100 kg | 15.75 st |
| 110 kg | 17.32 st |
Typical Body Weight Examples
👶 Child (8 years old)
4 stones = 25.4 kg
≈ 56 pounds
👧 Teenager
9 stones = 57.2 kg
≈ 126 pounds
👩 Average Woman (UK)
11 stones = 69.9 kg
≈ 154 pounds
👨 Average Man (UK)
13 stones = 82.6 kg
≈ 182 pounds
Quick Facts
UK Standard
1 stone = exactly 14 pounds = 6.35 kg
Body Weight Unit
Commonly used in UK and Ireland
Historical Unit
Dating back to medieval times
Conversion Tips
1 stone ≈ 6.35 kg (easy to remember)
To convert st to kg: multiply by 6.35
To convert kg to st: divide by 6.35
UK scales often show both units
Understanding Stones and Kilograms
What is a Stone?
The stone is a traditional British unit of weight used primarily for measuring body weight. It equals 14 pounds (lb) or approximately 6.35 kilograms. The stone has been used in the British Isles since medieval times and remains the preferred unit for expressing human body weight in the United Kingdom and Ireland.
Common Uses:
- •Personal body weight measurements (UK/Ireland)
- •Medical records and health assessments
- •Bathroom scales and weight tracking
- •Weight loss and fitness programs
What is a Kilogram?
The kilogram (kg) is the base unit of mass in the International System of Units (SI). It is defined by the International Prototype of the Kilogram and is used worldwide as the standard unit for measuring weight and mass. One kilogram equals 1,000 grams or approximately 2.20462 pounds.
Global Applications:
- •International standard for weight measurement
- •Medical and scientific applications worldwide
- •Food packaging and nutrition labels
- •Commercial trade and manufacturing
The Math Behind the Conversion
Understanding the Conversion Factor
The conversion between stones and kilograms is based on the pound as an intermediate unit:
1 stone = 14 pounds (exactly)
1 pound = 0.45359237 kg (exactly)
Therefore: 1 stone = 14 × 0.45359237 = 6.35029318 kg
Reverse conversion:
1 kg = 1 ÷ 6.35029318 ≈ 0.157473 stones
Step-by-Step Conversion Examples
Example 1: Convert 10 stones to kg
10 stones × 6.35029318 = 63.5029318 kg
Result: approximately 63.5 kg
Example 2: Convert 70 kg to stones
70 kg ÷ 6.35029318 = 11.0231 stones
Result: approximately 11 stones (or 11 st 0.3 lb)
Example 3: Convert 90 kg to stones and pounds
90 kg ÷ 6.35029318 = 14.1747 stones
Whole stones: 14 st
Decimal part: 0.1747 × 14 lb = 2.45 lb
Result: 14 stones 2.45 pounds
Quick Estimation Method
Stones to kg: Multiply by 6.35 (or 6.4 for quick mental math)
Kg to stones: Divide by 6.35 (or multiply by 0.16 for approximation)
Memory tip: Think "6 and a bit" - one stone is roughly 6.4 kilograms, making it easy to estimate body weight conversions in your head!
Regional Usage and Context
🇬🇧 United Kingdom
Stones remain the dominant unit for body weight:
- Personal bathroom scales show stones and pounds
- NHS (National Health Service) records use stones
- Fitness and diet programs reference stones
- Media and advertising use stones for weight
- Weighing scales in gyms display stones
🇮🇪 Ireland
Mixed usage of stones and kilograms:
- Stones commonly used for personal weight
- Medical records increasingly use kilograms
- Dual-unit scales are common
- Younger generation more familiar with kg
- Gradual shift toward metric system
🌍 Rest of World
Kilograms are the universal standard:
- All medical and scientific contexts use kg
- International trade uses metric system
- Food packaging shows weight in kg/g
- Sports and athletics use kilograms
- Stone rarely used outside UK/Ireland
💡 Why This Matters
Understanding both units is important for:
- Traveling between UK/Ireland and other countries
- Reading international health information
- Understanding medical documentation
- Online shopping for clothing and equipment
- Following international fitness programs
Body Weight Ranges by Age and Gender
| Category | Typical Range (Stones) | Typical Range (Kilograms) |
|---|---|---|
| Child (5-10 years) | 3-5 stones | 19-32 kg |
| Teenager (13-17 years) | 7-11 stones | 44-70 kg |
| Adult Woman (UK average) | 10-12 stones | 64-76 kg |
| Adult Man (UK average) | 12-14 stones | 76-89 kg |
| Athlete (varies by sport) | 11-16 stones | 70-102 kg |
*These are general ranges and can vary significantly based on height, body composition, and individual factors.
Frequently Asked Questions
How many kilograms are in a stone?
One stone equals exactly 6.35029318 kilograms. For practical purposes, you can use 6.35 kg as the conversion factor. This is based on the definition that 1 stone = 14 pounds, and 1 pound = 0.45359237 kg.
Why does the UK use stones for body weight?
The stone has been used in the British Isles since medieval times as a unit of weight. While the UK officially adopted the metric system in 1965, stones remained the preferred unit for personal body weight due to cultural tradition and familiarity. Many UK residents find stones more intuitive for tracking their weight than kilograms.
How do I convert 70 kg to stones and pounds?
To convert 70 kg to stones and pounds:
- Divide 70 by 6.35029318 to get stones: 70 ÷ 6.35 ≈ 11.02 stones
- The whole number is the stones: 11 stones
- Multiply the decimal part (0.02) by 14 to get pounds: 0.02 × 14 ≈ 0.35 lb
- Result: 70 kg = 11 stones 0.35 pounds
What's the easiest way to estimate stones to kg?
For quick mental math, remember that 1 stone ≈ 6.4 kg (rounding 6.35 up). So to convert stones to kilograms, multiply by 6.4. For example: 10 stones × 6.4 ≈ 64 kg. To convert kg to stones, divide by 6.4. This gives you a close approximation that's easy to calculate in your head.
Are stones still commonly used today?
Yes, stones are still widely used in the United Kingdom and Ireland for measuring personal body weight. Most bathroom scales in these countries display weight in stones and pounds. However, in medical and scientific contexts, kilograms are increasingly used. Outside of UK and Ireland, stones are rarely used, with kilograms being the international standard.