Construction

Acreage Calculator

Enter a lot's length and width, or its total square footage directly, to calculate its size in acres — useful when a property listing gives dimensions but not acreage, or vice versa.

Lot dimensions

ft
ft
Acres
Enter your lot dimensions to calculate.

How the Acreage formula works

One acre is defined as exactly 43,560 square feet:

Acres = (Length × Width) / 43,560

Step-by-step calculation

  1. Multiply the lot's length by its width to get total square feet (skip this if you already have total square footage).
  2. Divide by 43,560, the number of square feet in one acre.

Worked example

A lot measuring 200 ft × 300 ft: Area = 200 × 300 = 60,000 ft². Acres = 60,000/43,560 ≈ 1.38 acres.

Frequently asked questions

Why is an acre exactly 43,560 square feet?

It's a historical unit originally based on the area a yoke of oxen could plow in a day, later standardized to a fixed value — 43,560 ft² is the modern legal definition used consistently in the US and several other countries.

Does an acre have to be a square shape?

No — an acre is a unit of area, not a fixed shape. A rectangular, irregular, or oddly-shaped lot can all be exactly one acre as long as the total area matches 43,560 square feet.