milligram  mg  1e06 kg  
carat (metric)  carat  2e04 kg  i carat (metric)
 Unit of mass used for diamonds and other precious stones. Jewelers everywhere now use a metric carat defined in 1907 to be exactly 200 milligrams.

gram  g  1e03 kg  
kilogram  kg  1 kg  i kilogram
 Base unit of mass in the SI and MKS versions of the metric system.

quintal  quintal  1e+02 kg  i quintal
 Metric unit of mass equal to 100 kilograms or approximately 220.4623 pounds.

ton (metric)  t  1e+03 kg  
atomic unit mass  u  1.66054e27 kg  i atomic unit mass

Unit of mass used by chemists and physicists for measuring the masses of atoms and molecules.
Careful experiments have measured the size of this unit;
the currently accepted value (1998) is 1.660 538 73 x 10^{24} grams.

grain  gr  6.47989e05 kg  i grain

The UK and USsytem of apothecaries weight units is based on the grain:
1 scruple = 20 grains
1 (apoth) drachm (UK) = 3 scruples
1 (ap) dram (US) = 3 scruples
1 apoth ounce (UK) = 8 drachms
1 ap ounce (US) = 8 drachms
[1 grain = (1/7000) lb]
For more info see pound

dram  dram  1.77185e03 kg  i dram
 Unit of weight in the traditional avoirdupois system equal to 1/16 ounce or 1/256 pound

ounce  oz  2.83495e02 kg  i ounce

The UK and USsystem of avoirdupois weight units is based on the pound lb:
1 pound = 7000 grains 1 ounce = 16 drams 1 pound = 16 ounces 1 stone = 14 pounds 1 quarter = 2 stones 1 hundredweight (UK) = 4 quarters 1 ton (UK) = 20 hundredweights (UK) For more info see pound

pound  lb  4.53592e01 kg  i pound

In 1959 the national laboratory of Australia, Canada, Great Brittan, New Sealand, USA and South Africa
have decided to define the weight of the pound for precision measurements as:
1 lb = 0,453 59237 kg Before the
Uklb = 0,453 592 338 kg and the
Uslb = 0,453 592 427 7 kg
For more info see ounce

stone  stone  6.35029 kg  i stone
 Traditional British unit of weight. The stone was standardized at 14 pounds avoirdupois or approximately 6.350 29 kilograms. The stone equal exactly 1/2 quarter or 1/8 hundredweight.

Quarter  Quarter  1.27006e+01 kg  
hundredweight US  hundredweight US  4.53592e+01 kg  i hundredweight US
 The U.S. hundredweight is equal to 100 pounds. British version is often called the long hundredweight and the American is called the short hundredweight or cental.

Hundredweight UK  Hundredweight UK  5.08023e+01 kg  i Hundredweight UK
 Traditional unit of weight equal to 1/20 ton UK or 112 pounds avoirdupois, about 50.8023 kg

USton  Uston  9.07185e+02 kg  i USton
 1 USton = 1 short (of nett) ton = 2000 lb
For more info see pound

UKton  Ukton  1.01605e+03 kg  i UKton
 1 UKton = 1 long (of gross) ton (US) = 2240 lb
For more info see pound
