An acre is defined as a land unit that is commonly used in the US customary and imperial systems of 66 by 660 feet (one chain by one furlong). An acre is a measure of volume used in many countries. Meaning “open field” is commonly used to measure tracts of land and was first defined back in the middle age for measuring the amount of land a yoke of oxen could plow in one day. With the International yard and pound agreement of 1959, the acre was determined to represent precisely 4,046.856 422 4 square meters, and the other measuring systems translated it accordingly.
Because we do not use just one unit of measurement globally, an acre is recognized as a statute measure in the United Kingdom, most countries of the former British Empire, and the United States. What should be noted, however, is that, while the measurement can be legally used for trade and measurements of tracts of land, it should only be given as secondary information and should not be used for land registration.
Considering that we no longer use yokes of oxen to measure land, you might be wondering how big is an acre. The measurement of an acre can be of any shape, not only rectangular. The only necessity is that it amounts to a total area of 43,560 square feet. To better visualize, imagine something like a football field without both end zones.
An acre is about 4,047 square meters, 43,560 square feet, around 40% of a hectare, 1/640 of a square mile. It is essential to check the documents for any land owned or bought, however, to make sure that the measurements are in acres and not commercial acres. For a commercial acre, there is a slightly different method of measurement.