Stones to Pounds Converter
Convert UK weight measurements instantly. Accurate, simple, free.
Common values: 1, 5, 10, 15, 20 stones
Note: 1 stone = 14 pounds. Add up to 13.99 extra pounds.
Common Weight Conversions
| Stones | Pounds | Kilograms | Common Usage |
|---|---|---|---|
| 1 st | 14 lb | 6.35 kg | Small weight loss |
| 5 st | 70 lb | 31.75 kg | Child’s weight |
| 10 st | 140 lb | 63.50 kg | Average adult |
| 15 st | 210 lb | 95.25 kg | Heavier adult |
| 20 st | 280 lb | 127.01 kg | Maximum lift |
Important: UK vs US Measurements
UK and US pounds are identical (1 lb = 0.45359237 kg), but stones are only used in the UK and Ireland. Americans don’t use stones – they measure weight directly in pounds. 1 stone always equals 14 pounds exactly.
Stones to Pounds Conversion Result
How Stones to Pounds Conversion Works
Converting stones to pounds is a straightforward mathematical process based on a fixed conversion factor. This conversion is essential for understanding UK and Irish weight measurements, particularly for personal weight tracking, medical purposes, and everyday calculations in regions where stones are commonly used.
Exact Conversion Formula:
pounds = stones × 14
1 stone always equals exactly 14 pounds. This is a fixed, non-decimal conversion.
The Exact Conversion Mathematics
One stone equals exactly 14 pounds. This conversion is unique because it’s based on a historical British unit that was standardized in the 14th century. Unlike metric conversions that use decimal factors, the stone-to-pound conversion uses a simple whole number multiplier.
Country-Specific Usage and Examples
United Kingdom Usage
In the UK and Ireland, people commonly describe their weight in stones and pounds. For example, someone might say they weigh “11 stone 6” meaning 11 stones and 6 pounds. This system is used in everyday conversation, medical settings, and media. However, official medical records often use kilograms.
- Personal weight tracking and weight loss goals
- Baby weight measurements (often in pounds only)
- Sports and boxing weight classes
- Grocery items and produce (often in pounds or kilograms)
- Medical prescriptions and dosage calculations
UK Health Example:
A person weighs 13 stone 4 pounds. Converting to pounds: (13 × 14) + 4 = 182 + 4 = 186 pounds. Their doctor records this as 84.37 kilograms in their medical file.
United States Usage
Americans do not use stones. They measure weight exclusively in pounds. When Americans encounter stone measurements (usually from UK sources), they need to convert to pounds to understand the weight. This often happens when:
- Reading British news articles about weight loss
- Understanding UK fitness and health information
- Communicating with British friends about weight
- Reading historical documents or literature
- Watching British TV shows or movies
Canada Usage
Canada officially uses metric (kilograms) but many people, especially older generations, understand pounds. Stones are rarely used except when dealing with UK measurements. Canadians might need conversions when:
- Reading British publications
- Communicating with UK relatives
- Understanding historical weight references
- Working with UK-based health information
Canadian Example:
A Canadian reads that a British boxer weighs 14 stone 7 pounds. Converting: (14 × 14) + 7 = 196 + 7 = 203 pounds. Converting to metric: 203 × 0.453592 = 92.08 kilograms.
Australia Usage
Australia uses metric exclusively. Stones are only encountered in historical contexts or UK references. Australians converting stones typically need it for:
- Understanding British weight references
- Reading historical documents
- Communicating with UK contacts
- Academic research involving UK data
Practical Applications for Different Users
For Health and Fitness Tracking
People tracking weight loss or fitness progress often need to convert between stones and pounds. Many UK fitness apps and scales show stones and pounds, while international platforms use pounds or kilograms.
Health Tip: When setting weight loss goals, remember that 1 stone equals 14 pounds. Losing 1 stone is a significant milestone equivalent to 6.35 kilograms. This helps set realistic, measurable goals.
For Medical and Healthcare
Medical professionals in the UK often convert between stones/pounds and kilograms for accurate dosing and record-keeping. Medication dosages are typically calculated using metric weights.
Medical Example:
A patient weighs 12 stone 8 pounds. The nurse converts this to pounds: (12 × 14) + 8 = 168 + 8 = 176 pounds. For medication calculation, this converts to 79.83 kilograms using the exact conversion factor.
For Sports and Athletics
Boxing and wrestling weight classes in the UK often use stones, while international competitions use kilograms. Athletes and coaches need accurate conversions for training and competition preparation.
For Cooking and Recipes
While most modern recipes use metric or avoirdupois weights, historical British recipes might reference stones for larger quantities, especially for preserving or bulk cooking.
Common Questions About Stone to Pound Conversion
Why does 1 stone equal 14 pounds?
The stone was historically used for weighing commodities like wool, and different regions used stones of different weights. In 1389, a royal statute fixed the stone of wool at 14 pounds. This standardization made trade easier and eventually became the standard for all goods.
How do I convert stones and pounds to just pounds?
Multiply the stones by 14, then add any additional pounds. Example: 9 stone 11 pounds = (9 × 14) + 11 = 126 + 11 = 137 pounds. Our calculator does this automatically when you use the optional pounds field.
Why don’t Americans use stones?
The United States never adopted the stone as an official unit. After gaining independence, the US standardized on the avoirdupois system using pounds as the primary unit for body weight. Cultural separation and different standardization processes led to this divergence.
Are UK and US pounds the same?
Yes, since 1959, the international avoirdupois pound has been standardized as exactly 0.45359237 kilograms in both the UK and US. Before 1959, there were slight differences, but today they are identical.
How accurate do I need to be for weight conversions?
For personal weight tracking, rounding to the nearest pound is usually sufficient. For medical purposes, use exact conversions. For medication dosing, always use the exact kilogram conversion (1 lb = 0.45359237 kg exactly).
Technical Details and Historical Context
The stone has a long history in British measurement systems:
1 stone = 14 pounds (standardized in 1389)
1 pound = 16 ounces (avoirdupois system)
1 pound = 0.45359237 kilograms (international standard since 1959)
Therefore: 1 stone = 14 × 0.45359237 = 6.35029318 kilograms
The stone was officially abolished for trade in the UK in 1985 under the Weights and Measures Act, but it remains in common use for body weight measurement. The metric system (kilograms) is now the official standard, but cultural persistence keeps stones in everyday use.
Historical Development
The stone originated from the practice of using actual stones as weights. Different commodities had different stone weights until standardization. The wool stone (14 pounds) eventually became the standard for all goods. Regional variations existed until the 19th century when the imperial system was standardized.
Common Conversion Mistakes to Avoid
Critical Errors to Watch For:
- Thinking 1 stone equals 10 pounds (it’s 14)
- Adding pounds incorrectly when converting stones and pounds
- Confusing stones with kilograms in medical contexts
- Using approximate conversions for medication dosing
- Forgetting that stones are only used in UK/Ireland
Verification Method
Always verify your conversion by doing the reverse calculation. If 10 stone = 140 pounds, then 140 pounds should convert back to 10 stone (140 ÷ 14 = 10 exactly). For stones and pounds: 11 stone 6 = 160 pounds, then 160 ÷ 14 = 11 with 6 remainder.
Quick Reference Table for Common Weights:
Special Applications and Considerations
Weight Loss Tracking
When tracking weight loss in stones and pounds:
- Losing 1 stone = losing 14 pounds = 6.35 kg
- Common goal: lose “half a stone” (7 pounds or 3.18 kg)
- Many UK weight loss programs use stone increments
- Fitness trackers often need conversion settings adjusted
Baby Weight Measurements
In the UK, baby weights are typically measured in pounds and ounces, not stones. Newborns usually weigh 5-10 pounds (2.3-4.5 kg). The stone unit becomes relevant as children grow older.
Newborn: 7 lb 8 oz (3.4 kg)
6 months: 16 lb (7.3 kg) = approximately 1 stone 2 lb
1 year: 22 lb (10 kg) = approximately 1 stone 8 lb
Sports Weight Classes
Boxing weight classes in the UK traditionally used stones:
- Flyweight: 8 stone (112 lb / 50.8 kg)
- Featherweight: 9 stone (126 lb / 57.2 kg)
- Welterweight: 10 stone 7 (147 lb / 66.7 kg)
- Heavyweight: 14 stone 4 (200 lb / 90.7 kg) and above
Medical Dosage Calculations
For accurate medication dosing, precise conversions are essential:
Medical Calculation Example:
A medication dosage is 5 mg per kg of body weight. A patient weighs 13 stone 2 pounds. Converting: (13 × 14) + 2 = 184 pounds. Converting to kg: 184 × 0.45359237 = 83.46 kg. Dosage: 83.46 × 5 = 417.3 mg.
Everyday UK Expressions
Common UK expressions involving stones:
“I need to lose a few stone” = significant weight loss needed
“He’s over 20 stone” = very heavy (280+ pounds)
“She’s just 8 stone” = quite light (112 pounds)
“Half a stone lighter” = 7 pounds weight loss
About This Conversion Tool
This stones to pounds converter provides instant, accurate conversions using the exact conversion factor (1 stone = 14 pounds). Designed for UK residents, travelers, healthcare professionals, and anyone needing to understand or convert British weight measurements. The tool handles stones and additional pounds, and provides both pounds and kilograms for practical use. No registration required, no tracking, just precise calculations when you need them. Works completely offline after loading.