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Common Conversion Factors

Approximate Conversions from Metric to U.S. Customary Measures


Length


Symbol When You Know Multiply By To Find Symbol
mm millimeters 0.04 inches in
cm centimeters 0.4 inches in
m meters 3.3 feet ft
m meters 1.1 yards yd
km kilometers 0.6 miles mi


Area


Symbol When You Know Multiply By To Find Symbol
cm² square centimeters 0.16 square inches in²
square meters 1.2 square yards yd²
km² sqaure kilometers 0.4 square miles mi²
ha hectares
(10,000 m2)
2.5 acres


Mass (weight)


Symbol When You Know Multiply By To Find Symbol
g grams 0.035 ounces oz
kg kilograms 2.2 pounds lb
  metric ton
(1,000 kg)
1.1 short tons


Volume


Symbol When You Know Multiply By To Find Symbol
mL milliliters 0.03 fluid ounces fl oz
mL milliliters 0.06 cubic inches in³
L liters 2.1 pints pt
L liters 1.06 quarts qt
L liters 0.26 gallons gal
cubic meters 35 cubic feet ft³
cubic meters 1.3 cubic yards yd³


Temperature (exact)


Symbol When You Know Multiply By To Find Symbol
°C degrees Celsius 9/5, add 32 degrees Fahrenheit °F

K

Kelvin

subtract 273.15

degrees Celsius

°C


Note: These conversion factors are published as NIST SP 365, which is a laminated metric conversion card. Copies of this publication can be requested by contacting theSI@nist.gov

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