Units Conversion 

for Model Flyers

OANDA Currency Converter
Conversion Links
Fundamental Physical Constants
OUTFO - Fundamental Physical Constants
The CGS Units
A good little program for units conversion: Convert, by Josh Madison

Page with a script to convert units

(send me a hint if you think something is missing or in error)
No responsibility assumed for the correctness.

QuantityAlso EqualsEqual toSI Unit, comments
Length  meter (m)
1 mm .03937 in.exact by definition in USA until 1959
1 inch (in) 25.4 mmexact by definition in UK since 1933, and USA since 1959
1 foot (ft)12 in.3048 mexact
1 yard (yd)3 ft.9144 mexact
1 meter 3.28084 ft
1 mile1760 yards1.609344 kmexact
1 nautical mile 1852 mexact by definition
Area  square meter (m2)
1 sq.inch  645.16 mm2exact
1 dm2 15.500031 sq.inch
1 sq.foot .0929034 m2exact
1 sq.yard .83612736 m2exact
Volume  cubic meter (m3)
1 cm3 .06102 cu.in.
1 cu.in 16.387064 cm3exact
1 cu.foot 28.317 liters
1 US pint .473176 liter
1 imperial pint .56825 liter
1 liter1 dm3.264172 US gallon
1 US gallon (liquid)8 US pints, 231 cu.in3.785411784 liters exact
1 imperial gallon8 imp. pints (10 lbs of water)4.54609 liters
Mass  kilogram (kg)
1 ounce (oz) 28.349523 grams
1 pound (lb)16 ounces.45359237 kgexact
1 kg 2.20462 pounds(Originally the mass of 1 dm3 [liter] of water at a certain
temperature; Now the mass of a prototype in Paris)
Density  kilogram per cubic meter (kg/m3)
1 g/cm3 1.730 ounces per cu.in(for most materials)
1 g/dm3 .06243 pounds per cu.ft(for balsa)
Surface Weight  kilogram per square meter
1 oz. per sq.yd 33.906 g/m2(The units we use for covering materials)
1 g/m2 .0295 oz. per sq.yd
Speed  meter per second (m/s)
1 km/h .62137 mph
1 mph 1.609344 km/h
1 mph .44704 m/s
1 m/s 3.6 km/h
1 m/s 2.236932 mph
Mach 1speed of sound1225.1 km/h @ 15 °C
cspeed of light in vacuum299792458 m/sexact by definition
Pressure, Stress  pascal (Pa) = Newton per square meter (N/m2)
1 torr1 mm Hg133 Pa
1 psi 6894.757 Pa
1 bar100 000 Pa14.504 psi
1 kgf/cm2 98 066.5 Pa
1 atmosphere101325 Pa  exact by definition
1 atmosphere760 torr14.696 psi
Force  Newton (N)
1 N .1019716 kgf
1 N .2248 pound force
Energy  joule (J) = Newtonmeter (Nm) = Wattsecond (Ws)
1 foot pound (ft-lb) 1.355 818 J
1 kJ1 kWs.9478 BTU
Power  watt (W) = Joule per second (J/s)
1 horsepower (hp)1980000 ft-lbs per hr745.70 W
1 metric hp75 kgm/s735.5 W
1 BTU/sec1054.118 W
TemperatureConversion FormulaKelvin (K) or degree Celsius (°C)
{°F}{°F} = {°C} * 9 / 5 + 32
{°C}{°C} = ({°F} - 32) * 5 / 9
{K}{K} = {°C} + 273.15

Conversion Links

Science Fair Projects - Conversion Quite an exhaustive list of units.
Temperature Conversion Calculator Page
Pete Soule's Conversions Page
How Many? A Dictionary of Units of Measurement
Conversion Factors by Photobiology Online
MatWeb's Conversion Factors for Engineering Units
Metric Handbook from US Bureau of Land Management
More about the Metric System by Jacques J. Proot