SI* (Modern Metric) Conversion Factors
| APPROXIMATE CONVERSIONS TO SI
UNITS |
| SYMBOL |
WHEN YOU KNOW |
MULTIPLY BY |
TO FIND |
SYMBOL |
|
LENGTH
|
|
in
|
inches |
25.4 |
millimeters |
mm |
|
ft
|
feet |
0.305 |
meters |
m |
|
yd
|
yards |
0.914 |
meters |
m |
|
mi
|
miles |
1.61 |
kilometers |
km |
|
AREA
|
|
in2
|
square
inches |
645.2 |
square
millimeters |
mm2 |
|
ft2
|
square
feet |
0.093 |
square
meters |
m2 |
|
yd2
|
square
yard |
0.836 |
square
meters |
m2 |
|
ac
|
acres |
0.405 |
hectares |
ha |
|
mi2
|
square
miles |
2.59 |
square
kilometers |
km2 |
|
VOLUME
|
|
fl oz
|
fluid
ounces |
29.57 |
milliliters |
mL |
|
gal
|
gallons |
3.785 |
liters |
L |
|
ft3
|
cubic
feet |
0.028 |
cubic
meters |
m3 |
|
yd3
|
cubic
yards |
0.765 |
cubic
meters |
m3 |
|
NOTE: volumes greater than 1000 L shall
be shown in m3
|
|
MASS
|
|
oz
|
ounces |
28.35 |
grams |
g |
|
lb
|
pounds |
0.454 |
kilograms |
kg |
|
T
|
short tons
(2000 lb) |
0.907 |
megagrams
(or "metric ton") |
Mg (or
"t") |
| TEMPERATURE
(exact degrees) |
|
oF
|
Fahrenheit |
5 (F-32)/9
or (F-32)/1.8
|
Celsius |
oC |
|
ILLUMINATION
|
|
fc
|
foot-candles |
10.76 |
lux |
lx |
|
fl
|
foot-Lamberts |
3.426 |
candela/m2 |
cd/m2 |
|
FORCE and PRESSURE or STRESS
|
|
lbf
|
poundforce |
4.45 |
newtons |
N |
|
lbf/in2
|
poundforce
per square inch |
6.89 |
kilopascals |
kPa |
| APPROXIMATE CONVERSIONS FROM SI
UNITS |
|
SYMBOL |
WHEN
YOU KNOW |
MULTIPLY BY |
TO
FIND |
SYMBOL |
|
LENGTH
|
|
mm
|
millimeters |
0.039
|
inches |
in |
|
m
|
meters |
3.28
|
feet |
ft |
|
m
|
meters |
1.09
|
yards |
yd |
|
km
|
kilometers |
0.621
|
miles |
mi |
|
AREA
|
|
mm2
|
square
millimeters |
0.0016
|
square
inches |
in2 |
|
m2
|
square
meters |
10.764
|
square
feet |
ft2 |
|
m2
|
square
meters |
1.195
|
square
yards |
yd2 |
|
ha
|
hectares |
2.47
|
acres |
ac |
|
km2
|
square
kilometers |
0.386
|
square
miles |
mi2 |
|
VOLUME
|
|
mL
|
milliliters |
0.034
|
fluid
ounces |
fl oz |
|
L
|
liters |
0.264
|
gallons |
gal |
|
m3
|
cubic
meters |
35.314
|
cubic
feet |
ft3 |
|
m3
|
cubic
meters |
1.307
|
cubic
yards |
yd3 |
|
MASS
|
|
g
|
grams |
0.035
|
ounces |
oz |
|
kg
|
kilograms |
2.202
|
pounds |
lb |
|
Mg (or "t")
|
megagrams
(or "metric ton") |
1.103
|
short
tons (2000 lb) |
T |
|
TEMPERATURE (exact degrees)
|
|
oC
|
Celsius |
1.8C+32 |
Fahrenheit |
oF |
|
ILLUMINATION
|
|
lx
|
lux |
0.0929
|
foot-candles |
fc |
|
cd/m2
|
candela/m2 |
0.2919
|
foot-Lamberts |
fl |
|
FORCE and PRESSURE or STRESS
|
|
N
|
newtons |
0.225 |
poundforce |
lbf |
|
kPa
|
kilopascals |
0.145
|
poundforce per square inch |
lbf/in2 |
*SI is the symbol for the International System of Units. Appropriate rounding should be made to comply with Section 4 of ASTM E380. (Revised March 2003)
