Deprecated units

These units are not suitable for scientific work and should only be used for converting old material or when dictated by legal or other special requirements.

For scientific use see International system of units.

Length

• 1 mile (mi) = 1609.344 meter (exactly)
• 1 yard (yd) = 0.9144 meter (exactly)
• 1 foot (ft) = 0.3048 meter (exactly)
• 1 inch (in) = 0.0254 meter (exactly)
• 1 micron (µ) = 1 micrometer (exactly)
• 1 light year (l.y.) = 9.460 73 x 10¹⁵m
• 1 parsec (pc) = 3.086 x 10¹⁵m

Area

• 1 square inch = 6.4516 square centimeters (exactly)
• 1 square foot = 0.092 903 square meter
• 1 circular mil = 5.0671 x 10^-4 square millimeter
• 1 acre = 4046.9 square meters
• 1 barn = 10^-28 square meter (exactly)
• 1 hectare = 10 000 square meters (exactly)

Volume

• 1 cubic inch = 16.387 cubic centimeters
• 1 cubic foot = 0.028 317 cubic meter
• 1 fluid ounce (UK) = 28.413 cubic centimeters
• 1 fluid ounce (US) = 29.574 cubic centimeters
• 1 gallon (UK) = 4546.1 cubic centimeters
• 1 gallon (US) = 3785.4 cubic centimeters
• 1 barrel (US) (for petroleum; etc) = 0.158 99 cubic meter
• 1 acre foot = 1233.5 cubic meters
• 1 liter = 1000 cubic centimeters (exactly)

Temperature

• Fahrenheit

From	To
	Degree Celsius	Kelvin	Fahrenheit
Degree Celsius	n/a	<math>K = {}^\circ C + 273.15</math>	<math>F = {}^\circ C \times \frac{9}{5}+32</math>
Kelvin	<math>{}^\circ C = K - 273.15</math>	n/a	<math>F = (K - 273.15) \times \frac{9}{5} + 32</math>
Fahrenheit	<math>{}^\circ C = \frac {(F - 32)} {\frac{9}{5}} </math>	<math>K = \frac {(F - 32)} {\frac{9}{5}} + 273.15 </math>	n/a

Speed

• 1 foot per minute = 5.08 millimeters per second (exactly)
• 1 mile per hour = 0.447 04 meter per second (exactly)
• 1 knot = 0.514 44 meter per second
• 1 kilometer per hour = 0.277 78 meter per second

Mass

• 1 ounce (avoirdupois) = 28.350 grams
• 1 pound = 0.453 59 kilogram
• 1 slug = 14.594 kilograms
• 1 short ton = 907.18 kilograms
• 1 long ton = 1016.0 kilograms

Density

• 1 pound per cubic foot = 16.018 kilograms per cubic meter
• 1 pound per cubic inch = 27 680 kilograms per cubic meter

Force

• 1 poundal = 0.138 25 newton
• 1 ounce-force = 0.278 01 newton
• 1 pound-force = 4.4482 newtons
• 1 kilogram-force = 9.806 65 newtons (exactly)
• 1 dyne = 10^-5 newton (exactly)

Pressure

• 1 poundal per square foot = 1.4882 pascals (newtons per square meter)
• 1 pound-force per square foot = 47.880 pascals
• 1 pound-force per square inch = 6894.8 pascals
• 1 conventional foot of water = 2989.1 pascals
• 1 conventional millimeter of mercury = 133.32 pascals
• 1 torr = 101325 / 760 pascals (exactly). Its value differs from the conventional millimetre of mercury by about 1 part in 7 million.
• 1 conventional millimetre of mercury (mmHg) = 133.32 pascals
• 1 conventional inch of mercury (inHg) = 3 386.39 pascals
• 1 standard atmosphere (760 torr) = 101 325 pascals (exactly)
• 1 technical atmosphere (1 kgf/cm²) = 98 066.5 pascals (exactly)

Energy, Work

• 1 foot poundal = 0.042 140 joule
• 1 foot pound-force = 1.3558 joules
• 1 British thermal unit (thermochemical) = 1054 joules
• 1 British thermal unit (International Table) = 1055 joules
• 1 calorie (thermochemical) = 4.184 joules (exactly)
• 1 calorie (International Table) = 4.1868 joules (exactly)
• 1 erg = 10^-7 joule (exactly)

Power

• 1 foot pound-force per second = 1.3558 watts
• 1 horsepower (metric) = 735.50 watts
• 1 horsepower (British) = 745.70 watts
• 1 horsepower (electrical) = 746 watts (exactly)
• 1 British thermal unit (International Table) per hour = 0.2931 watt
• 1 erg per second = 10^-7 watt (exactly)

Quantities of Light

• 1 footcandle = 10.764 lux (lumens per square meter)
• 1 footlambert = 3.4263 candelas per square meter

Quantities of Electricity and Magnetism

• 1 ESU of current 3.3356 x 10^-10 ampere
• 1 EMU of current = 10 amperes (exactly)
• 1 ESU of electric potential 299.79 volts
• 1 EMU of electric potential = 10^-8 volt (exactly)
• 1 ESU of capacitance 1.1126 x 10^-12 farad
• 1 EMU of capacitance = 10⁹ farads (exactly)
• 1 ESU of inductance 8.9876 x 10¹¹ henrys
• 1 EMU of inductance = 10^-9 henry (exactly)
• 1 ESU of resistance 8.9876 x 10¹¹ ohms
• 1 EMU of resistance = 10^-9 ohm (exactly)
• 1 gilbert 0.795 77 ampere
• 1 oersted 79.577 amperes per meter
• 1 maxwell = 10^-8 weber (exactly)
• 1 gauss = 10^-4 tesla (exactly)

Note that ESU means electrostatic CGS unit; EMU means electromagnetic CGS unit. In this list, the sign is to be read “corresponds to.” Since the change from either CGS system to the International System of Units involves a change in quantities, conversion of units by multiplication by a pure number is not, strictly speaking, possible. However, a physical situation which can be described as a “current” of 1 abampere can also be described as a current of 10 amperes.