Metric - US/Imperial Conversion Charts

Length :: Area :: Volume/Capacity :: Mass (weight) :: Temperature

If you need to convert from Imperial or US Standard units to Metric, or the other way around, one of the tables below should help. Or you can use our Unit Converter

Example 1: Convert 500 millimeters to inches:

500 mm x 0.03937 = 19.7 inches

Example 2: Convert 500 millimeters to feet:

500 mm x 0.03937 = 19.7 inches, and there are 12 inches in a foot, so

19.7/12 = 1.64 feet (or 1 foot and 7.7 inches)

Note: values are accurate to 4 significant digits only.

Length

Metric   US or Imperial
1 millimeter [mm]   arrow 0.03937 in
1 centimeter [cm] 10 mm arrow 0.3937 in
1 meter [m] 100 cm arrow 1.0936 yd
1 kilometer [km] 1000 m arrow 0.6214 mile

 

US or Imperial   Metric
1 inch [in]   arrow 2.54 cm
1 foot [ft] 12 in arrow 0.3048 m
1 yard [yd] 3 ft arrow 0.9144 m
1 mile 1760 yd arrow 1.6093 km
1 int nautical mile 2025.4 yd arrow 1.853 km
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Area

Metric   US or Imperial
1 sq cm [cm2] 100 mm2 arrow 0.1550 in2
1 sq m [m2] 10,000 cm2 arrow 1.1960 yd2
1 hectare [ha] 10,000 m2 arrow 2.4711 acres
1 sq km [km2] 100 ha arrow 0.3861 mile2

 

US or Imperial   Metric
1 sq inch [in2]   arrow 6.4516 cm2
1 sq foot [ft2] 144 in2 arrow 0.0929 m2
1 sq yd [yd2] 9 ft2 arrow 0.8361 m2
1 acre 4840 yd2 arrow 4046.9 m2
1 sq mile [mile2] 640 acres arrow 2.59 km2
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Volume/Capacity

Metric   US Measure Imperial
1 cu cm [cm3]   arrow 0.0610 in3
1 cu decimeter [dm3] 1,000 cm3 arrow 0.0353 ft3
1 cu meter [m3] 1,000 dm3 arrow 1.3080 yd3
1 liter [l] 1 dm3 arrow 2.113 fluid pt 1.7598 pt

 

US Measure Imperial   Metric
1 cu inch [in3] arrow 16.387 cm3
1 cu foot [ft3] arrow 0.02832 m3
1 fluid ounce 1.0408 UK fl oz arrow 29.574 ml
1 pint (16 fl oz) 0.8327 UK pt arrow 0.4732 liters
1 gallon (231 in3) 0.8327 UK gal arrow 3.7854 liters
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Mass

Metric   US or Imperial
1 milligram [mg]   arrow 0.0154 grain
1 gram [g] 1,000 mg arrow 0.0353 oz
1 kilogram [kg] 1,000 g arrow 2.2046 lb
1 tonne [t] 1,000 kg arrow 1.1023 short ton
1 tonne [t] 1,000 kg arrow 0.9842 long ton

 

US or Imperial   Metric
1 ounce [oz] 437.5 grain arrow 28.35 g
1 pound [lb] 16 oz arrow 0.4536 kg
1 stone 14 lb arrow 6.3503 kg
1 hundredweight [cwt] 112 lb arrow 50.802 kg
1 short ton (US)   arrow 0.9072 t
1 long ton (UK)   arrow 1.0160 t
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Temperature

To convert from Celsius to Fahrenheit, first multiply by 9/5, then add 32.
To convert from Fahrenheit to Celsius, first subtract 32, then multiply by 5/9

(To find out why, visit the Temperature Conversion page)

History of Measurement

Years ago people came up with standard length measures, but they didn't all agree on one system.

The Imperial System (which uses yards, feet, inches, etc to measure length) was developed over hundreds of years in the UK, then the French developed the Metric System (meters) in 1670, which soon spread through Europe, even to England itself in 1963. But the USA and a few other countries still prefer feet and inches.