Useful Conversion Factors
The
following factors are provided to
10
digits
of
accuracy
where possible.
Exact
values are marked with an asterisk.
For
more complete information
on
conversion factors, refer to
Metric Practice Guide E380-74 by the American Society for
Testing and Materials
(ASTM)
.
Length
1
inch
1
foot
1 mile (statute)t
1 mile
(nautical)t
1 mile (statute)t
Area
1
square
inch
1 square
foot
1 acre
1
square
mile
t
Volume
1
cubic
inch
1
cubic
foot
1
ounce
(fluid)
t
1
ounce
(fluid)t
1
gallon
(fluid)
t
Mass
= 25.4
millimeters'
=
0.3048
meter'
=
1.609344
kilometers
'
= 1.852
kilometers'
=
1.150779448
miles
(nauticallt
= 6.451 6
square
centimeters'
= ·
0.09290304
square
meter
'
=
43560
square
feet
= 640
acres
=
16.387064
cubic
centi
meters'
=
0.028316847
cubic
meter
=
29.57352956
cubic
centimeters
=
0.029573530
liter
= 3.785411 784
liters'
1
ounce
(mass) =
28.34952312
grams
1
pound
(mass) =
0.45359237
kilogram
'
1
ton
(short) =
0.90718474
metric
ton'
Energy
1
British
thermal
unit
1
kilocalorie
(mean)
= 1
055.055853
joules
=
4190.02
joules
1
watt-hour
=
3600
joules
'
Force
1
ounce
(force) =
0.27801385
newton
1
pound
(force)
= 4.448221 615
newtons
Power
1
horsepower
(electric)
= 746
watts
'
Pressure
1
atmosphere
1
atmosphere
1
atmosphere
Temperature
Fahrenheit
Celsius
kelvin
kelvin
kelvin
= 760
mm
Hg at sea level
= 14.7
pounds
per square
inch
=
101
325 pascals
= 1.8
Celsius
+ 32
= 5/
9(Fahrenheit
- 32)
= Celsius
+ 273.15
= 5/9
(Fahrenheit
+ 459.67)
= 5/9
Rankine
t U.S. values chosen.
'Exact
values.