Conversions From

Imperial Units 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

Length

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

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

oF

Fahrenheit

(F-32) x 5 / 9

Celsius

oC

Illumination

fc

foot-candles

10.76

lux

lx

fl

foot-Lamberts

3.426

candela/m²

cd/m²

Force & Pressure or Stress

lbf

poundforce

4.45

newtons

N

lbf/in²

poundforce per square inch

6.89

kilopascals

kPa