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Office of the Chief Financial Officer

Doing Business with FHWA

Laws, Code, and Regulations Guidance and Questions and Answers Transparency Funding and Reports Doing Business with FHWA

Contract Related Forms and Publications

SI* (MODERN METRIC) Conversion Factors

APPROXIMATE CONVERSIONS TO SI UNITS

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOLSYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
LENGTH
ininches25.4millimetersmmmmmillimeters0.039inchesin
ftfeet0.305metersmmmeters3.28feetft
ydyards0.914metersmmmeters1.09yardsyd
mimiles1.61kilometerskmkmkilometers0.621milesmi

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOLSYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
AREA
in2square inches645.2square millimetersmm2mm2square millimeters0.0016square inchesin2
ft2square feet0.093square metersm2m2square meters10.764square feetft2
yd2square yard0.836square metersm2m2square meters1.195square yardsyd2
acacres0.405hectareshahahectares2.47acresac
mi2square miles2.59square kilometerskm2km2square kilometers0.386square milesmi2

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOLSYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
VOLUME
fl ozfluid ounces29.57 millilitersmLmLmilliliters0.034fluid ouncesfl oz
gal gallons3.785litersLLliters0.264gallonsgal
ft3cubic feet0.028cubic metersm3m3cubic meters35.314cubic feetft3
yd3cubic yards0.765cubic metersm3m3cubic meters1.307cubic yardsyd3

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOLSYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
MASS
ozounces28.35gramsgggrams0.035ouncesoz
lbpounds0.454kilogramskgkgkilograms2.202poundslb
Tshort tons (2000 lb)0.907megagrams (or "metricton")Mg (or "t")Mg (or "t")megagrams (or "metric ton")1.103short tons (2000 lb)T

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOLSYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
TEMPERATURE (exact degrees)
°FFahrenheit5 (F-32)/9 or (f-32)/1.8Celsius°C°CCelsius1.8C+32Fahrenheit°F

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOLSYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
ILLUMINATION
fcfoot-candles10.76luxlxlxlux0.0929foot-candlesfc
flfoot-Lamberts3.426candela/m2cd/m2cd/m2candela/m20.2919foot-Lambertsfl

SYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOLSYMBOLWHEN YOU KNOWMULTIPLY BYTO FINDSYMBOL
FORCE and PRESSURE or STRESS
lbfpoundforce4.45newtonsNNnewtons0.225poundforcelbf
lbf/in2poundforce per square inch6.89kilopascalskPakPakilopascals0.145poundforce per square inchlbf/in2

NOTE: volumes greater than 1000 L shall be shown in m3

*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
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000