What this conversion means in practice
This page focuses on one job: converting pound to stone quickly and correctly. That sounds simple, but the context matters. People use this specific conversion for body weight logging, food prep, shipping labels, fitness programming, and product specifications that mix metric and US customary units in the same workflow.
If you are moving between systems often, it helps to remember the fixed ratio: 1 lbs = 0.071428571429 st. Once that ratio is clear, you can sanity-check numbers before copying them into spreadsheets, forms, or reports. For example, converting a small quantity should stay small, and converting a larger value should scale proportionally. If a result looks wildly off, it is usually a misplaced decimal, the wrong unit (such as troy ounce vs avoirdupois ounce), or a typo in the source value.
The converter above and the lookup table below are designed for fast checks, while the notes on each unit help with documentation, training, and technical writing where unit definitions need to be explicit.
Pound
Definition: The international avoirdupois pound (lb) is defined exactly as 0.45359237 kilograms. One pound equals exactly 16 avoirdupois ounces.
History and origin: The modern pound descends from the Roman libra through many regional variants. In 1959, English-speaking countries agreed on the exact kilogram definition used today, standardizing trade and engineering calculations.
Current use: Pounds are widely used in the United States for body weight, groceries, and household measurements. They also remain visible in UK labeling and in global contexts where US customary units are common.
Stone
Definition: A stone (st) is a British imperial unit equal to exactly 14 pounds, or 6.35029318 kilograms.
History and origin: Stone once varied by commodity and region in Britain. Over time, legal and commercial standards fixed it at 14 pounds for consistent measurement.
Current use: Stone is still commonly used in the UK and Ireland for body weight, often alongside pounds (for example, 11 st 4 lb).
How to convert pound to stone
Multiply the pound value by 0.071428571429 to get stone.
Example: 15 lbs × 0.071428571429 = 1.071428571429 st
Pound to Stone conversion table
| Pound (lbs) | Stone (st) |
|---|---|
| 0.1 lbs | 0.0071428571 st |
| 1 lbs | 0.0714285714 st |
| 2 lbs | 0.1428571429 st |
| 3 lbs | 0.2142857143 st |
| 5 lbs | 0.3571428571 st |
| 10 lbs | 0.7142857143 st |
| 20 lbs | 1.4285714286 st |
| 50 lbs | 3.5714285714 st |
| 100 lbs | 7.1428571429 st |
| 1,000 lbs | 71.4285714286 st |
Pound to Stone FAQ
Is this conversion factor exact?
It depends on the pair. Many unit relationships are exact by definition (for example, pound to kilogram is fixed exactly), while displayed decimals are rounded for readability.
How many decimals should I keep?
Use more decimals for scientific work and fewer for consumer-facing labels. For most daily use, 2 to 3 decimals is enough. Regulatory, medical, and engineering contexts may require stricter precision rules.
What is the most common mistake with this conversion?
The most common issue is mixing unit systems or abbreviations that look similar. Always confirm the source unit first, then convert once. Double-conversion errors are common when values are copied between tools.