Acreage Calculator
Find the acreage of a lot or field from its measurements (rectangle, triangle or circle) or from GPS points around it.
Change the values and press Calculate to work out your own figures.
Length and width
Enter the length and width.
Show the working
- acres = square feet ÷ 43,560
Three sides
Enter the three sides.
Show the working
- acres = square feet ÷ 43,560
Round area
Enter the diameter.
Show the working
- acres = square feet ÷ 43,560
GPS points
Enter the latitude and longitude of each corner, in order around the lot.
Show the working
- points projected onto a local plane (WGS 84 radii at the mean latitude), then the shoelace formula
How to use it
Enter the length and width. Enter the three sides. Enter the diameter. Enter the latitude and longitude of each corner, in order around the lot.
Lengths can be decimals, fractions or tape entries such as 12' 6 1/2" (in feet or inches). Prices are optional.
Key facts
acres = square feet ÷ 43,560 (1 acre = 4,046.8564224 m²) GPS: points projected to a local plane, then area = ½ |Σ (xᵢ yᵢ₊₁ − xᵢ₊₁ yᵢ)|
Getting GPS points
In most map apps, press and hold on a corner to see its latitude and longitude. Walk or click the corners in order, all the way round.
Lot sizes
A quarter acre is 10,890 sq ft (a square about 104 ft on a side); an acre is 43,560 sq ft, for example 66 × 660 ft.
Questions
How many acres is 33 × 102 ft?
0.0773 acres.
How many square feet in an acre?
43,560.
Formulas
acres = square feet ÷ 43,560 (1 acre = 4,046.8564224 m²) GPS: points projected to a local plane, then area = ½ |Σ (xᵢ yᵢ₊₁ − xᵢ₊₁ yᵢ)|
Sources
Limitations
- Material densities are typical values (the midpoint of the commonly published range); real loads vary with moisture, grading and compaction, so check with your supplier or type in their density.
- Tank results are the geometric volume; real tanks have wall thickness and fittings.