Acreage Calculator
Convert acres, square feet, square meters, hectares, and square miles, turn lot dimensions into acres, and see how deep a lot of a given size runs from the road.
Convert an area
- Square feet
- 43,560
- Square yards
- 4,840
- Square meters
- 4,047
- Hectares
- 0.4047
- Square miles
- 0.0015625
Lot dimensions to acres
For a rectangular lot. Irregular parcels need the acreage from the survey or the deed.
Often the road frontage.
- Acres
- 2
- Square feet
- 87,120
- Square meters
- 8,094
How deep is a lot of a given size?
Enter the acreage and the road frontage to see how far back a rectangular lot would run.
- Depth needed
- 435.6 ft
- If it were square
- 208.7 ft per side
The definitions behind the numbers
Every conversion on this page uses the unit definitions published by the National Institute of Standards and Technology in Handbook 44. An acre is 43,560 square feet. A square mile is 640 acres. A hectare is 10,000 square meters, which works out to about 2.471 acres. Feet are converted to meters with the international foot, exactly 0.3048 meters.
Common sizes at a glance
| Size | Equals |
|---|---|
| 1/4 acre | 10,890 sq ft |
| 1/2 acre | 21,780 sq ft |
| 1 acre | 43,560 sq ft |
| 5 acres | 217,800 sq ft |
| 10 acres | 435,600 sq ft |
| 40 acres | a quarter of a quarter section |
| 160 acres | a quarter section |
| 640 acres | one section, one square mile |
Why acreage matters when you buy land
Listings round. A parcel advertised as five acres may be 4.6 on the deed, and the price per acre changes accordingly. Compare the acreage in the listing, the deed, and the county tax records, and when the price depends on it, let the survey settle the number. Our guide to finding property lines explains how legal descriptions state a parcel's size, and the due diligence checklist covers the rest of what to verify.
Zoning also sets minimum lot sizes, often in acres, for building a home or installing a septic system. A parcel just under the minimum may not be buildable at all, so the county planning office is the place to confirm the number that applies.
Frequently asked questions
How big is an acre in feet?
An acre is 43,560 square feet. A square acre measures about 208.7 feet on each side. Acres are rarely square, though: a lot 100 feet wide needs to run 435.6 feet deep to reach one acre.
How many acres are in a square mile?
There are 640 acres in a square mile. In the Public Land Survey System used across most of the western and southern United States, a section is one square mile, so a quarter section is 160 acres and a quarter of a quarter section is 40 acres.
What is the difference between an acre and a hectare?
A hectare is a metric unit equal to 10,000 square meters. One hectare is about 2.47 acres, and one acre is about 0.405 hectare. Land in the United States is sold by the acre, while most other countries use hectares.
How many square feet is a quarter acre or a half acre?
A quarter acre is 10,890 square feet and a half acre is 21,780 square feet. Many suburban building lots fall in that range, while rural parcels are usually described in whole acres.
Source: NIST Handbook 44, Appendix C, General Tables of Units of Measurement, National Institute of Standards and Technology.