AreaMapAcreage calculator
Enter the length and width of a rectangular lot or field to get its size in acres, hectares and square feet. Know the square footage already? Use the second calculator. For an odd-shaped lot, measure it on a satellite map instead.
How acreage is calculated
One acre is 43,560 square feet, which is about 4,047 square meters or 0.405 hectares. To get acres, multiply the length by the width to get square feet, then divide by 43,560.
Example: a lot 210 ft wide and 210 ft deep is 210 × 210 = 44,100 ft². Divided by 43,560, that’s 1.01 acres.
In metric, one hectare is 10,000 m² and equals 2.471 acres.
Common lot sizes
| Acres | Square feet | Square of side | Hectares |
|---|---|---|---|
| ¼ acre | 10,890 ft² | 104 × 104 ft | 0.10 ha |
| ½ acre | 21,780 ft² | 148 × 148 ft | 0.20 ha |
| 1 acre | 43,560 ft² | 209 × 209 ft | 0.40 ha |
| 2 acres | 87,120 ft² | 295 × 295 ft | 0.81 ha |
| 5 acres | 217,800 ft² | 467 × 467 ft | 2.02 ha |
| 10 acres | 435,600 ft² | 660 × 660 ft | 4.05 ha |
| 40 acres | 1,742,400 ft² | 1,320 × 1,320 ft | 16.19 ha |
Lots that aren’t rectangles
Most real lots and fields have more than four sides, or sides that aren’t square. Length × width overstates them. You can split the shape into rectangles and triangles and add them up (a triangle is half its base × its height), or trace the boundary on a satellite map and let the app do the geometry. Our guide on how to measure acreage walks through every method.
Questions
How many square feet are in an acre?
An acre is exactly 43,560 square feet. That’s the same as 4,840 square yards, or about 4,047 square meters.
How big is an acre?
About 209 by 209 feet if it were a square. An American football field without the end zones is 48,000 ft², so an acre is about 90% of one.
How many acres is a hectare?
One hectare is 2.471 acres, and one acre is 0.405 hectares.
How do I find the acreage of an irregular lot?
Trace its boundary on a satellite map. In AreaMap you tap each corner and the app calculates the exact area on the curved Earth, in acres or hectares. You can also split the lot into rectangles and triangles and add them up.