1609
Square measure
1 square millimetre = 0.00155 square inch
100 mm² = 1 square centimetre = 0.1550 square inch
10 cm² = 1 square metre = 1.196 square yards
100m² = 1 are = 119.6 square yards
100 ares = 1 hectare = 2.471 acres
100 ha = 1 square kilometre = 247.1 acres
Cubic measure
1 cubic centimetre = 0.06102 cubic inch
1000 cm³ = 1 cubic decimetre = 0.03532 cubic foot
1000 dm³ = 1 cubic metre = 1.308 cubic yards
Circular measure
1 microradian = 0.206 seconds
1000 µrad = 1 milliradian = 3.437 minutes
1000 mrad = 1 radian = 57.296 degrees
= 180/π degrees
Metric preferences
Abbreviation Factor
tera- T 10¹²
giga- G 10⁹
mega- M 10⁶
kilo- k 10³
hecto- h 10²
deca- d 10¹
deci- d 10⁻¹
centi- c 10⁻²
milli- m 10⁻³
micro- µ 10⁻⁶
nano- n 10⁻⁹
pico- p 10⁻¹²
femto- f 10⁻¹⁵
atto- a 10⁻¹⁸
Units of length
1 inch = 2.54 cm
12 inches = 1 foot = 0.3048 m
3 feet = 1 yard = 0.9144 m
5½ yards = 1 rod, pole or perch = 5.029 m
22 yards = 1 chain = 20.12 m
10 chains = 1 furlong = 0.2012 km
8 furlongs = 1 mile = 1.609 km
6076.12 feet = 1 nautical mile = 1852 m
Units of weight
1 grain = 64.8 mg
1 dram = 1.772 g
16 drams = 1 ounce = 28.35 g
16 ounces = 1 pound = 0.4536 kg
14 pounds = 1 stone = 6.350 kg
2 stones = 1 quarter = 12.70 kg
4 quarters = 1 (long)
hundredweight = 50.80 kg
20 hundredweight = 1 (long) ton = 1.016 tonnes
100 pounds = 1 (short)
hundredweight = 45.36 kg
2000 pounds = 1 (short) ton = 0.9072 tonnes
The short hundredweight and ton are more common
in the US
Units of capacity
1 fluid ounce = 28.41 cm³
5 fluid ounces = 1 gill = 0.1421 dm³
4 gills = 1 pint = 0.5683 dm³
2 pints = 1 quart = 1.137 dm³
4 quarts = 1 (UK) gallon = 4.546 dm³
231 cubic inches = 1 (US) gallon = 3.785 dm³
8 gallons = 1 bushel = 36.369 dm³
Square measure
1 square inch = 645.16 mm²
144 square inches = 1 square foot = 0.0929 m²
9 square feet = 1 square yard = 0.8361 m²
4840 square yards = 1 acre = 4047 m²
640 acres = 1 square mile = 259 ha
Cubic measure
1 cubic inch = 16.39 mm³
1728 cubic inches = 1 cubic foot = 0.02832 m³
= 28.32 dm³
27 cubic feet = 1 cubic yard = 0.7646 m³
= 764.6 dm³
Circular measure
1 second = 4.860 µrad
60 seconds = 1 minute = 0.2909 µrad
60 minutes = 1 degree = 17.45 µrad
= π/180 rad
45 degrees = 1 oxtant = π/4 rad
60 degrees = 1 sextant = π/3 rad
90 degrees = 1 quadrant or
1 right angle = π/2 rad
360 degrees = 1 circle or
1 circumference = 2π rad
1 grade or gon = 1/100th of a
right angle = π/200 rad
US dry measure
1 pint = 0.9689 UK pint = 0.5506 dm³
1 bushel = 0.9689 UK bushel = 35.238 dm³
US liquid measure
1 fluid ounce = 1.0408 UK fluid ounces
= 0.0296 dm³
16 fluid ounces = 1 pint = 0.8327 UK pint
= 0.4732 dm³
8 pints = 1 gallon = 0.8327 UK gallon
= 3.7853 dm³
Temperature
° Fahrenheit = (9/5 x °C) + 32
° Celsius = 5/9 (°F - 32)