What is stone?
A stone is a unit of mass used primarily in the United Kingdom and Ireland, equal to 14 pounds. It is mainly used to express human body weight in everyday conversation.
Real-world uses
The stone is used primarily in the UK and Ireland for expressing body weight (e.g., "I weigh 11 stone"). It appears on bathroom scales sold in Britain and is the preferred unit in British medical consultations for patient weight discussions.
History
The stone has been used in the British Isles since at least the 14th century for weighing agricultural goods. Its value varied historically (from 4 to 32 pounds depending on the commodity) before being fixed at 14 pounds by the Weights and Measures Act of 1835.
Common mistakes
Assuming a stone is used outside the British Isles—it is virtually unknown in the US, continental Europe, or most other countries. Also, forgetting that 1 stone = 14 pounds, not 10 or 12.
What is gram?
A gram is a metric unit of mass equal to one thousandth of a kilogram. It is widely used in cooking, food labelling, and the measurement of small quantities in science and pharmacy.
Real-world uses
Grams are used for food nutrition labelling, postal weight limits, cooking recipes (especially in baking where precision matters), and jewellery weights. Pharmacists measure drug dosages in grams and fractions thereof.
History
The gram was the original base unit of mass in the French metric system of 1795, defined as the mass of one cubic centimetre of water. It later became the base unit in the CGS system before the kilogram took precedence in SI.
Common mistakes
Confusing grams with grains (1 grain ≈ 0.065 g), a common error in pharmaceutical contexts. Also, mistaking "g" for "G" in digital contexts where G means giga.
When is this conversion used?
Converting between stone and gram is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region. Cooking recipes and food packaging often switch between grams and ounces, especially when adapting recipes from different culinary traditions.
Worked examples
1 stone = 6,350.29318 gram
1 gram = 0.001 kilogram
How to convert stone to gram
To convert stone to gram, multiply the value by 6,350.29318.
To convert gram back to stone, multiply by 0.00015747.
Measurement standards
The kilogram is defined by fixing the Planck constant to exactly 6.62607015 × 10⁻³⁴ joule-seconds, as established at the 26th General Conference on Weights and Measures in 2018. This ended the last SI definition based on a physical artefact.
Did you know?
The International Prototype of the Kilogram, a platinum-iridium cylinder stored near Paris since 1889, was found to have drifted by about 50 micrograms relative to its copies over a century — roughly the mass of a fingerprint.
Quick reference: stone to gram
| stone | gram |
|---|---|
| 0.1 | 635.029318 |
| 0.5 | 3,175.14659 |
| 1 | 6,350.29318 |
| 2 | 12,700.58636 |
| 5 | 31,751.4659 |
| 10 | 63,502.9318 |
| 25 | 158,757.3295 |
| 50 | 317,514.659 |
| 100 | 635,029.318 |
| 250 | 1,587,573.295 |
| 500 | 3,175,146.59 |
| 1,000 | 6,350,293.18 |
Common values
| stone | gram | |
|---|---|---|
| A paperclip | 0.15747304 stone | 1,000 gram |
| A smartphone | 27.55778277 stone | 175,000 gram |
| A bag of sugar | 0.15747304 stone | 1,000 gram |
| Average adult human | 11.02311311 stone | 70,000 gram |
| A small car | 188.9676533 stone | 1,200,000 gram |