Archilinks
Imperial Equivalents
Linear
1 foot = 12 inches1 yard = 3 feet = 36 inches
1 chain = 22 yards = 66 feet = 2 376 inches
1 furlong = 10 chains = 220 yards = 660 feet = 23 760 inches
1 (statute) mile = 8 furlongs = 80 chains = 1 760 yards = 5 280 feet = 63 360 inches
1 nautical mile = 2 025 yards = 6 075 feet = 72 900 inches
Area
1 square foot = 144 square inches1 square yard = 9 square feet = 1 296 square inches
1 acre = 4 840 square yards = 43 560 square feet = 6 272 640 square inches
Volume
1 cubic foot = 1 728 cubic inches1 cubic yard = 27 cubic feet = 46 656 cubic inches
Liquid Volume
1 pint = 16 ounces1 quart = 2 pints = 32 ounces
1 gallon = 4 quarts = 8 pints = 128 ounces
Weight / Mass
1 pound = 16 ounces1 ton = 2 000 pounds = 32 000 ounces
Metric Equivalents
Linear
1 centimeter = 10 milimeters1 decimeter = 10 centimeters = 100 millimeters
1 meter = 10 decimeters = 100 centimeters = 1 000 millimeters
1 kilometer = 1 000 meters = 10 000 decimeters = 100 000 centimeters = 1 000 000 millimeters
Area
1 square centimeter = 100 square millimeters1 square decimeter = 100 square centimeters = 10 000 square millimeters
1 square meter = 100 square decimeters = 10 000 square centimeters = 1 000 000 square millimeters
1 are = 100 square meters = 10 000 square decimeters = 1 000 000 square centimeters
1 hectare = 10 ares = 10 000 square meters
1 square kilometer = 100 hectares = 10 000 ares = 1 000 000 square meters
Volume
1 cubic centimeter = 1 000 cubic millimeters1 cubic decimeter = 1 000 cubic centimeters = 1 000 000 cubic millimeters
1 cubic meter = 1 000 cubic decimeters = 1 000 000 cubic centimeters = 1 000 000 000 cubic millimeters
Weight / Mass
1 gram = 1 000 milligrams1 kilogram = 1 000 grams = 1 000 000 milligrams
1 tonne = 1 000 kilograms = 1 000 000 grams = 1 000 000 000 milligrams
Metric / Imperial Conversions
The United States has yet to change to the metric system due, in part, to the challenge in converting to another system because the grids of materials will not simply and rationally convert. There are two methods for converting: soft conversions and hard conversions.
Soft Conversions
Soft conversions from imperial to metric represent an exact conversion where the material dimension has not changed. For instance, 12 inches would have a soft conversion of 304.8 millimeters. Occasionally, the soft conversion will be rounded so that 12 inches has a soft conversion of 305 millimeters.Hard Conversions
Hard conversions from imperial to metric are used in the building industry to make the metric units more rational. For instance, 12 inches would have a hard conversion of 300 millimeters. In this case, the actual dimension of the material changes so that building materials can easily conform to metric grids.Imperial to Metric Soft Conversions
| Length | Area | Volume |
| 1 inch = 25.4 mm | 1 sq. in. = 645.16 mm2 | 1 cu inch = 16.387 cm3 |
| 1 foot = 304.8 mm | 1 sq ft = 0.093 m2 | 1 cu foot = 28316.847 cm3 |
| 1 yard = 914.4 mm | 1 sq yard = 0.836 m2 | 1 cu yard = .7646 m2 |
| 1 mile = 1.609 km | 1 acre = 4046.86 m2 | 1 gallon = 3.785 L |
| 1 sq mile = 2.59 km2 |
Metric to Imperial Soft Conversions
| Length | Area | Volume |
| 1 mm = 0.0394 in | 1 mm2 = 0.00155 sq in | 1 m3 = 35.3147 cu ft |
| 1 m = 3.281 ft | 1 m2 = 10.7639 sq ft | 1 L = 0.264172 gallons |
| 1 km = 0.621 mi. | 1 hectare = 2.47105 acres | |
| 1 km2 = 0.368 sq miles |
