Lot dimensions to area

Land Square Footage Calculator

Calculate a rectangular lot or split an L-shaped/simple compound area into up to three rectangles. Add the sections, subtract any known excluded area, then see square feet, acres, square yards and square metres.

Calculate land square footage

Area 1

Optional Area 2

Optional Area 3

Optional: subtract a cutout only when you already know its square footage.
Measure irregular lot on map
Enter dimensions above.

How to calculate square footage of land

For a rectangle, multiply length × width. A 100 ft × 100 ft lot contains 10,000 square feet. To convert that result to acres, divide by 43,560.

For a simple L-shaped yard or lot, divide the shape into non-overlapping rectangles, calculate each rectangle separately and add the areas together. This calculator provides three rectangular sections so you can do that without a separate spreadsheet.

Example: two rectangular sections

Main rectangle100 × 80 ft

8,000 sq ft.

Second rectangle40 × 30 ft

1,200 sq ft.

Total9,200 sq ft

About 0.2112 acres before any excluded area.

When the rectangle method is not enough

The rectangle method is convenient when your measurements actually describe rectangular sections. It becomes weak when a parcel has angled boundaries, curves, many corners or uncertain property lines. For those situations, trace the polygon on a map or work from a reliable survey.

Also remember that square footage measures area. It does not automatically tell you perimeter, fence length or whether a project fits in a particular part of the lot. Those questions need the actual shape and dimensions.

Frequently asked questions

How do I turn lot dimensions into acres?

Calculate square feet first, then divide by 43,560. For example, 150 × 200 ft = 30,000 sq ft, which is about 0.6887 acres.

Can I add two rectangles together?

Yes, if they represent separate non-overlapping parts of the same area. Calculate each area and add them.

Can I use this for an irregular lot?

Only if the lot can reasonably be split into rectangles. Otherwise use the map or irregular-lot tool.

Does this calculate legal lot size?

No. It calculates from the dimensions you enter. Legal boundary area should be verified from authoritative records or a survey when the decision depends on it.

Have only a map or address?

Trace the real property shape instead of guessing length and width.

Measure Property