Acreage Calculator
Land gets measured in feet but bought and sold by the acre, and the conversion isn't one most people carry in their head. Enter your lot's length and width below, or switch to a circle or triangle for an odd-shaped parcel. You'll get the size in acres, square feet, square yards, and hectares at once, so you can talk to a seller, a county office, or a surveyor in whatever unit they use.
How big your lot is, in every unit at once
An acre is 43,560 square feet, but a listing might quote square feet, a deed might quote acres, and a fence quote comes back in linear feet. Enter your lot dimensions and this tool gives the size in acres, square feet, square yards, hectares, and square meters at the same time, so you're never the one doing a second conversion at the closing table.
The math
For a rectangular lot, multiply length by width for square feet, then divide by 43,560 for acres. That single number, 43,560, is the one to remember. Everything else is a conversion off the square footage, and the calculator runs all of them at once.
| One acre equals |
|---|
| 43,560 square feet |
| 4,840 square yards |
| 4,046.86 square meters |
| 0.4047 hectare |
| 1/640 of a square mile |
What an acre actually looks like
An acre is close to 90 percent of an American football field between the goal lines, or a square about 208.7 feet on each side. That square has a perimeter near 835 feet, which is the number you want when you're pricing fence. The shape can be anything, though; only the area makes it an acre.
Measuring an irregular lot
Few lots are clean rectangles. For an odd shape, break it into rectangles and triangles, figure each one, and add them up. A rectangle is length times width; a triangle is half its base times its height. Add the pieces for total square footage, then divide by 43,560. For a four-sided lot with no square corners, measuring from the corner points and summing the parts gets you close enough to plan around.
| Lot portion | Square feet | Square side |
|---|---|---|
| 1/4 acre | 10,890 | ~104 ft |
| 1/3 acre | 14,520 | ~120 ft |
| 1/2 acre | 21,780 | ~148 ft |
| 1 acre | 43,560 | ~209 ft |
A real example
A 150 by 200 foot lot is 30,000 square feet. Divide by 43,560 and it's about 0.69 acre, just over two-thirds. The perimeter, if you're fencing it, is 150 plus 200 doubled, 700 linear feet. Enter your own numbers above and you get all the units without the longhand.
How accurate these numbers are
Tape measurements off straight sides are solid. Pacing a lot or tracing it on a phone map gets you within a percent or three, fine for planning a fence or a garden, not for a deed. When acreage drives a sale price or a loan, the figure that counts comes from a licensed survey. Use this to plan and to sanity-check, then verify before money changes hands. To price what you're looking at, run it through the price per acre calculator or check the average cost of an acre by state.
Common questions
An acre is 43,560 square feet. Picture a square about 209 feet on each side, or roughly 90% of an American football field including the end zones. It's a fixed area, not a shape, so an acre can be long and narrow or square.
Find the area in square feet (length times width for a rectangular lot), then divide by 43,560. Enter your dimensions above and the calculator does it, plus the conversions to hectares and square yards.
Break it into rectangles and triangles, calculate each with the shape option, and add them up. For a legal boundary, a licensed survey is the only number a county or lender will accept.
Exactly 43,560. That number never changes, which is why every acreage conversion runs through it.
Estimates for planning. Verify against your supplier's units and your local building codes before ordering or building. For anything structural, follow your engineer or local code.