Measures and weights
conversion table between US/GB and the Metric (SI) System:
(according to the Oxford Advanced Learner's Dictionary)

Metric --> US & GB
length
10 millimetres (mm) 1 centimetre (cm) 0.394 inch (in)
100 cm 1 metre (m) 39,4 inches or
1.094 yards (yd)
1000 m 1 kilometre (km) 0,6214 mile or
cca. 5/8 mile
surface
100 square m 1 are (a) 0,025 acre
100 ares 1 hectare (ha) 2,471 acres
100 hectares 1 square km 0,386 square mile
weight
10 milligrams (mg) 1 centigram (cg) 0,154 grain
100 centigrams 1 gram (g) 15,43 grains
100 grams 10 dekagram
(no SI measure, but often used in recipes!)
0,205 pound
1000 grams 1 kilogram (kg) 2,205 pounds
1000 kilograms 1 tonne (t) 19,688 hundredweight
capacity
1000 millilitres (ml) 1 litre (l) 1,76 pints
(2,1 US pints)
100 ml 1 decilitre (dl) (No SI measure, but often used in recipes) 0,176 pints
(0,21 US pints)
10 litres 1 decalitre 2,2 gallons
(2,63 US gallons)
temperature
Celsius or Centigrade (C) Fahrenheit (F)
Boiling-point 100 212
90 194
80 176
70 158
60 140
50 122
40 104
30 86
20 68
10 50
Freezing-point 0 32
-10 14
-17,8 0
Absolute Zero -273,15 -459,67

To convert Fahrenheit temperature into Celsius:
subtract 32 and multiply by 5/9 (five-ninths).

To convert Celsius temperature into Fahrenheit:
multiply by 9/5 (nine-fifths) and add 32.

US & GB --> Metric
length
1 inch 25,4 millimetres =
2,54 cm
12 inches 1 foot (ft) 30,48 centimetres
3 feet 1 yard (yd) 0,914 metre (m)
5 1/2 yards 1 rod, pole or perch 5,029 m
22 yards 1 chain (ch) 20,17 m
220 yards 1 furlong (fur) 201,7 m
8 furlongs 1 mile 1,609 kilometres (km)
1760 yards 1 mile 1,609 kilometres (km)
3 miles 1 league 4,828 km
surface
1 square inch 6,452 sq centimetres
144 sq inches 1 sq foot 929,03 sq centimetres
9 sq feet 1 sq yard 0,836 sq metre
434 sq yards 1 sq chain 404,62 sq metres
4840 sq yards 1 acre 0,405 hectare
40 sq rods 1 rood 10,1168 ares
4 roods 1 acre 0,405 hectare
640 acres 1 sq mile 2,59 sq kilometres or
259 hectares
weight (click here for conversion chart)
1 grain (gr) 0,065 gram (g)
437 1/2 grains 1 ounce (oz) 28,35 grams
16 drams (dr) 1 ounce 28,35 grams
16 ounces 1 pound (lb) 0,454 kilogram (kg) =
45,4 dekagram (dkg)
(No SI measure, but often used in recipes!)
14 pounds 1 stone (st) 6,356 kg
2 stone 1 quarter 12,7 kg
4 quarters 1 hundredweight (cwt) 50,8 kg
112 pounds 1 cwt 50,8 kg
100 pounds 1 short cwt 45,4 kg
20 cwt 1 ton 1016,04 kg
2000 pounds 1 short ton 0,907 tonne
2240 pounds 1 long ton 1,016 tonnes
capacity
GB US
4 gills 1 pint (pt) 1,201 pints 0,568 litre (l)
2 pints 1 quart (qt) 1,201 quarts 1,136 litres
4 quarts 1 gallon (gal) 1,201 gallons 4,546 litres
cubic measure
1 cubic inch 16,39 cu centimetres
1728 cu inches 1 cu foot 0,028 cu metre
27 cu feet 1 cu yard 0,765 cu metre
temperature
Fahrenheit (F) Celsius or Centigrade (C)
Boiling-point 212 100
194 90
176 80
158 70
140 60
122 50
104 40
86 30
68 20
50 10
Freezing-point 32 0
14 -10
0 -17,8
Absolute Zero -459,67 -273,15

To convert Fahrenheit temperature into Celsius:
subtract 32 and multiply by 5/9 (five-ninths).

To convert Celsius temperature into Fahrenheit:
multiply by 9/5 (nine-fifths) and add 32.