Foot
The foot is a unit of length equal to 12 inches, or exactly 0.3048 meters. It is abbreviated ft or marked with a single prime symbol ('). Three feet make one yard.
The international foot was fixed at exactly 0.3048 meters by an agreement among English-speaking countries in 1959. The United States also kept a slightly different survey foot for land surveying until it was retired at the end of 2022.
Dimensions in feet and inches are written with prime and double prime marks, so 12'6" means 12 feet 6 inches.
US floor plans usually give room dimensions in feet and inches. Convert the inches to a decimal before multiplying: 12'6" is 12.5 feet. See how to read floor plan measurements.
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