conversion from sq ft to acreage

i have converted my property into square feet. It measures 114,521.63 sq ft. When i use the conversion chart for acre(survey) i get 2.629 acres, but when you change it to acre(commercial) the result is 3.181. Can anyone tell me the difference between the two?

[Robert Fogt]

A commercial acre is an acre, minus the area used for the street, alley, sidewalk, etc. Used often in city areas to make the land seem bigger then it actually is.

For example, a 1 acre lot in the middle of the suburbs in the city may only really give you 0.8 acres to build on.

The survey acre is not used much anymore, you want to use the international acre. Though both are very close and you would still come out to 2.629 acres.

114 521.63 square foot = 2.629 054 867 acre