Commonly Used Conversion Factors

The table below is a guide to help calculate conversion of units, using common converting factors to convert area, volume, pressure, power, distance, and more .

Multiply:	By:	To Obtain:
Acres	43560	Square Feet
Acres	1.562 x 10^-3	Square Miles
Acre-Feet	43560	Cubic Feet
Amperes per sq cm	6.452	Amperes per sq in.
Amperes per sq in.	0.1550	Amperes per sq cm.
Ampere-Turns	1.257	Gilberts
Ampere-Turns per cm	2.540	Ampere-Turns per in.
Ampere-Turns per in.	0.3937	Ampere-Turns per cm.
Atmospheres	76.0	Cm of mercury
Atmospheres	29.92	Inches of mercury
Atmospheres	33.90	Feet of Water
Atmospheres	14.70	Pounds per sq in.
British thermal units	252.0	Calories
British thermal units	778.2	Foot-Pounds
British thermal units	3.960 x 10^-4	Horsepower-Hours
British thermal units	0.2520	Kilogram-calories
British thermal units	107.6	Kilogram-meters
British thermal units	2.931 x 10^-4	Kilowatt-hours
British thermal units	1055	Watt-seconds
Btu per hour	2.931 x 10^-2	Kilowatts
Btu per minute	2.359 x 10^-2	Horsepower
Btu per minute	1.759 x 10^-2	Kilowatts
Bushels	1.244	Cubic Feet
Multiply:	By:	To Obtain:
Centimeters	0.3937	Inches
Circular mils	5.067 x 10^-6	Square centimeters
Circular mils	0.7854 x 10^-6	Square inches
Circular mils	0.7854	Square mils
Cords	128	Cubic Feet
Cubic Centimeters	6.102 x 10^-6	Cubic Inches
Cubic feet	0.02832	Cubic meters
Cubic feet	7.481	Gallons
Cubic feet	28.32	Liters
Cubic Inches	16.39	Cubic centimeters
Cubic meters	35.31	Cubic feet
Cubic meters	1.308	Cubic yards
Cubic yards	0.7646	Cubic meters
Degrees [angle]	0.01745	Radians
Dynes	2.248 x 10^-6	Pounds
Ergs	1	Dyne-centimeters
Ergs	7.37 x 10^-6	Foot-pounds
Ergs	10^-7	Joules
Farads	10⁶	Microfarads
Fathoms	6	Feet
Feet	30.48	Centimeters
Feet of Water	.08826	Inches of mercury
Multiply:	By:	To Obtain:
Feet of Water	304.8	Kg per square meter
Feet of Water	62.43	Pounds per square ft.
Feet of Water	0.4335	Pounds per square in.
Foot-pounds	1.285 x 10^-2	British thermal units
Foot-pounds	5.050 x 10^-7	Horsepower-hours
Foot-pounds	1.356	Joules
Foot-pounds	0.1383	Kilogram-meters
Foot-pounds	3.766 x 10^-7	Kilowatt-hours
Gallons	0.1337	Cubic Feet
Gallons	231	Cubic Inches
Gallons	3.785 x 10^-3	Cubic Meters
Gallons	3.785	Liters
Gallons per minute	2.228 x 10^-3	Cubic Feet per second
Gausses	6.452	Lines per square in.
Gilberts	0.7958	Ampere-turns
Henries	10³	Millihenries
Horsepower	42.41	Btu per min
Horsepower	2544	Btu per hour
Horsepower	550	Foot-pounds per sec
Horsepower	33000	Foot-pounds per min
Horsepower	1.014	Horsepower (metric)
Horsepower	10.70	Kg calories per min
Horsepower	0.7457	Kilowatts
Multiply:	By:	To Obtain:
Horsepower (boiler)	33520	Btu per hour
Horsepower – hours	2544	British thermal units
Horsepower – hours	1.98 x 10⁶	Foot-pounds
Horsepower – hours	2.737 x 10⁵	Kilogram-meters
Horsepower – hours	0.7457	Kilowatt-hours
Inches	2.540	Centimeters
Inches of mercury	1.133	Feet of water
Inches of mercury	70.73	Pounds per square ft.
Inches of mercury	0.4912	Pounds per square in.
Inches of water	25.40	Kg per square meter
Inches of water	0.5781	Ounces per square in.
Inches of water	5.204	Pounds per square ft.
Joules	9.478 x 10^-4	British thermal units
Joules	0.2388	Calories
Joules	10⁷	Ergs
Joules	0.7376	Foot-Pounds
Joules	2.778 x 10^-7	Kilowatt-hours
Joules	0.1020	Kilogram-meters
Joules	1	Watt-seconds
Kilograms	2.205	Pounds
Kilogram-calories	3.968	British thermal units
Kilogram meters	7.233	Foot-pounds
Kg per square meter	3.281 x 10^-3	Feet of water
Multiply:	By:	To Obtain:
Kg per square meter	0.2048	Pounds per square ft.
Kg per square meter	1.422 x 10^-3	Pounds per square in.
Kilolines	10³	Maxwells
Kilometers	3.281	Feet
Kilometers	0.6214	Miles
Kilowatts	56.87	Btu per min
Kilowatts	737.6	Foot-pounds per second
Kilowatts	1.341	Horsepower
Kilowatts-hours	3.415	British thermal units
Kilowatts-hours	2.655 x 10⁶	Foot-pounds
Knots	1.152	Miles
Liters	0.03531	Cubic Feet
Liters	61.02	Cubic Inches
Liters	0.2642	Gallons
Log N_e or in N	0.4343	Log₁₀N
Log N	2.303	Log_e N or in N
Lumens per square ft.	1	Footcandles
Maxwells	10^-3	Kilolines
Megalines	10⁶	Maxwells
Megaohms	10⁶	Ohms
Meters	3.281	Feet
Meters	39.37	Inches
Meter-kilograms	7.233	Pound-feet
Multiply:	By:	To Obtain:
Microfarads	10^-6	Farads
Microhms	10^-6	Ohms
Microhms per cm cube	0.3937	Microhms per in cube
Microhms per cm cube	6.015	Ohms per mil foot
Miles	5280	Feet
Miles	1.609	Kilometers
Miner’s Inches	1.5	Cubic feet per min.
Ohms	10^-6	Megohms
Ohms	10⁶	Microhms
Ohms per mil foot	0.1662	Microhms per cm cube
Ohms per mil foot	0.06524	Microhms per in. cube
Poundals	0.03108	Pounds
Pounds	32.17	Poundals
Pound-feet	0.1383	Meter-kilograms
Pounds of water	0.01602	Cubic Feet
Pounds of water	0.1198	Gallons
Pounds per cubic foot	16.02	Kg per cubic meter
Pounds per cubic foot	5.787 x 10^-4	Pounds per cubic in.
Pounds per cubic inch	27.68	Grams per cubic cm.
Pounds per cubic inch	2.768 x 10^-4	Kg per cubic meter
Pounds per cubic inch	1.728	Pounds per cubic ft.
Pounds per square foot	0.01602	Feet of Water
Multiply:	By:	To Obtain:
Pounds per square foot	4.882	Kg per square meter
Pounds per square foot	6.944 x 10^-3	Pounds per sq. in.
Pounds per square inch	2.307	Feet of Water
Pounds per square inch	2.036	Inches of Mercury
Pounds per square inch	703.1	Kg per square meter
Radians	57.30	Degrees
Square centimeters	1.973 x 10⁵	Circular mils
Square Feet	2.296 x 10^-5	Acres
Square Feet	0.09290	Square meters
Square inches	1.273 x 10⁶	Circular mils
Square inches	6.452	Square centimeters
Square Kilometers	0.3861	Square miles
Square meters	10.76	Square feet
Square miles	640	Acres
Square miles	2.590	Square kilometers
Square Millimeters	1.973 x 10³	Circular mils
Square mils	1.273	Circular mils
Tons (long)	2240	Pounds
Tons (metric)	2205	Pounds
Tons (short)	2000	Pounds
Multiply:	By:	To Obtain:
Watts	0.05686	Btu per minute
Watts	10⁷	Ergs per sec
Watts	44.26	Foot-pounds per in
Watts	1.341 x 10^-3	Horsepower
Watts	14.34	Calories per min
Watts-hours	3.412	British thermal units
Watts-hours	2655	Footpounds
Watts-hours	1.341 x 10^-3	Horsepower-hours
Watts-hours	0.8605	Kilogram-calories
Watts-hours	376.1	Kilogram-meters
Webers	10⁸	Maxwells