Factors for Converting Units of MassThe factors in the tables below can be used to convert between units of mass or weight which are used in different parts of the world. Also old publications give units which are no longer used, so when preparing recipes or making up insecticides or weedikillers the correct amount can be found.
There is a great deal of interest at present in the Body Mass Index and the relationship to health. It is an expression of body weight in relation to height,, above certain levels the risk of heart disease and diabetes increases.
Use these links to other pages of conversion factors.
The calculator below can be dragged around with your mouse for working out your conversion.
Useful Weight Relationships
Imperial which uses Auoirdupois Weight
16 drams = 1 ounce (oz)
16 ounces = 1 pound (lb)
14 pounds = 1 stone (st)
28 pounds = 1 quarter (qr.)
4 quarters (112 pounds) = 1 hundredweight (cwt.)
20 hundredweight = 1 ton = 2240 lb (long).
1 kilogram = 1000 grams
1 tonne = 1000 kilograms
1 metric carat = 200 milligrams
3.17 grains = 1 carat
24 grains = 1 pennyweight (dwt.)
20 pennyweights = 1 ounce
12 ounces = 1 pound
100 pounds = 1 hundredweight
NB. The carat is the proportion of gold in the alloy used to make a article of jewellery. Articles are taken to consist of 24 carats and are quoted to contain 9, 15, 18 or 22 carats of gold, eg. one stamped 9 carats has 9 parts gold and 15 parts alloy. (A sovereign is 22 carat gold).
Apothecaries' weight - used in old Medical prescriptions
20 grains = 1 scruple ()
3 scruples = 1 drachm ()
8 drachms = 1 ounce ()
12 ounces = 1 pound.
Density - It is sometimes useful to know the weight of material when the volume required is known, This can be calculated from the Density
|Density = Mass|
| so Mass = Density x Volume.|
|Some density values|| || |
|Copper - pure||8900||kg/m3|
|Water (4 C)||999.97||kg/m3|
Mass (Weight) Conversion Factors
|grains (gr)||grams (g)||0.0647|
|ounces (oz) (avoirdupois)||grams||28.35|
|pounds (lb)||kilograms (kg)||0.4536|
|kilograms (kg)||pounds (lb)||2.2046|
|stones ||kilograms (kg)||6.3503|
|tonnes||tons (long 2240 lb)||0.9842|
|tonnes||tons (short 2000 lb)||1.1023|
For the more health conscoius here are a couple of Body Mass Index (BMI) calculators
Imperial or USA, with a comment from the Panel on Energy, Obesity, and
Body Weight Standards on your health category, published by the American
Journal of Clinical Nutrition.