Square Feet to Acres (sq ft to ac)
An acre is exactly 43,560 square feet (4,046.8564224 m², NIST SP 811), so divide square feet by 43,560. A 10,000 sq ft lot is 0.23 acres.
Formula
acres = sq ft ÷ 43,560
Example: 7,500 square feet = 0.172176 acres.
Square Feet to Acres chart
| square feet | acres |
|---|---|
| 1,000 | 0.022957 |
| 2,000 | 0.045914 |
| 5,000 | 0.114784 |
| 7,500 | 0.172176 |
| 8,000 | 0.183655 |
| 10,000 | 0.229568 |
| 10,890 | 0.25 |
| 15,000 | 0.344353 |
| 20,000 | 0.459137 |
| 21,780 | 0.5 |
| 30,000 | 0.688705 |
| 43,560 | 1 |
| 50,000 | 1.14784 |
| 87,120 | 2 |
| 100,000 | 2.29568 |
| 250,000 | 5.73921 |
| 500,000 | 11.4784 |
| 1,000,000 | 22.9568 |
Good to know
Lot sizes: listings often give the lot in square feet. A typical 8,000 sq ft suburban lot is 0.18 acres, 10,890 sq ft is exactly a quarter acre and 21,780 sq ft is half an acre. For a rectangle, multiply length × width in feet first: 100 × 150 ft = 15,000 sq ft = 0.344 acres.
House vs lot: a 2,000 sq ft house on one floor covers 0.046 acres, under 5% of an acre. Add the garage, drive and patio to see how much of the lot is left for lawn.
Survey feet: older US land records used the US survey foot, about 2 parts per million longer than the international foot, which made an acre about 0.0162 m² bigger. NIST and NOAA retired the survey foot at the end of 2022, so new work uses 43,560 international square feet.
Frequently asked questions
How many square feet make an acre?
Exactly 43,560 square feet.
How many acres is 10,000 square feet?
10,000 sq ft is 0.2296 acres — a little under a quarter acre.
How many acres is 100,000 square feet?
100,000 sq ft is 2.296 acres.
How do I find the acreage of a lot?
Multiply the length by the width in feet to get square feet, then divide by 43,560. A 120 × 200 ft lot is 24,000 sq ft, or 0.551 acres.