Convert square feet to acres


To convert square feet to acres, first you need to know how many square feet there are in an acre.

By definition 1 acre is equal to 43560 square feet.

This relationship between square feet and acres can help you convert any area that is in square feet to acres.

Example #1

Convert 87120 square feet to acres.

We can solve this problem by setting up a proportion.

If 43560  square feet is equal 1 acre

87120 square feet is equal to x acres

Here is table that summarizes this problem.

43560 1 acre
87120 x


The proportion is 43560 / 87120 = 1 acre / x

After cross multiplication, we get 43560 × x = 87120 × 1 acre

43560x = 87120 acres

x = 87120 acres / 43560

x = 2 acres

87120 square feet is equal to 2 acres.

Example #2

Convert 21780 square feet to acres.

Again, this problem can be solved by setting up a proportion.

If 43560  square feet is equal 1 acre

21780 square feet is equal to x acres

Here is table that summarizes this problem.

43560 1 acre
21780 x


The proportion is 43560 / 21780 = 1 acre / x

After cross multiplication, we get 43560 × x = 21780 × 1 acre

43560x = 21780 acres

x = 21780 acres / 43560

x = 0.5 acres

21780 square feet is equal to 0.5 acres.




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