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Acquisition and Grants Management

SI* (MODERN METRIC) Conversion Factors

APPROXIMATE CONVERSIONS TO SI UNITS

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
LENGTH
ininches25.4millimetersmm
ftfeet0.305metersm
ydyards0.914metersm
mimiles1.61kilometerskm

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
AREA
in2squareinches645.2square millimetersmm2
ft2squarefeet0.093square metersm2
yd2square yard0.836square metersm2
acacres0.405hectaresha
mi2square miles2.59square kilometerskm2

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
VOLUME
fl ozfluid ounces29.57millilitersmL
galgallons3.785litersL
ft3cubic feet0.028cubic metersm3
yd3cubic yards0.765cubic metersm3
NOTE: volumes greater than 1000 L shall be shown in m3

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
MASS
ozounces28.35gramsg
lbpounds0.454kilogramskg
Tshort tons (2000 lb)0.907megagrams (or "metric ton")Mg (or "t")

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
TEMPERATURE (exact degrees)
oFFahrenheit5 (F-32)/9
or (F-32)/1.8
CelsiusoC

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
ILLUMINATION
fcfoot-candles10.76luxlx
flfoot-Lamberts3.426candela/m2cd/m2

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
FORCE and PRESSURE or STRESS
lbfpoundforce4.45newtonsN
lbf/in2poundforce per square inch6.89kilopascalskPa

APPROXIMATE CONVERSIONS TO SI UNITS

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
LENGTH
mmmillimeters0.039inchesin
mmeters3.28feetft
mmeters1.09yardsyd
kmkilometers0.621milesmi

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
AREA
mm2square millimeters0.0016square inchesin2
m2square meters10.764square feetft2
m2square meters1.195square yardsyd2
hahectares2.47acresac
km2square kilometers0.386square milesmi2

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
VOLUME
mLmilliliters0.034fluid ouncesfl oz
Lliters0.264gallonsgal
m3cubic meters35.314cubic feetft3
m3cubic meters1.307cubic yardsyd3

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
MASS
ggrams0.035ouncesoz
kgkilograms2.202poundslb
Mg (or "t")megagrams (or "metric ton")1.103short tons (2000 lb)T

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
TEMPERATURE (exact degrees)
oCCelsius1.8C+32 FahrenheitoF

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
ILLUMINATION
lx lux0.0929foot-candlesfc
cd/m2candela/m20.2919foot-Lambertsfl

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
FORCE and PRESSURE or STRESS
Nnewtons0.225poundforcelbf
kPakilopascals0.145poundforce per square inchlbf/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)

Page last modified on November 1, 2012.
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