How to Calculate Acreage: Formula & Land Measurement Guide

If you are buying land, fencing a lot, or estimating sod for a large yard, you need to know how to calculate acreage. An acre is simply a unit of land area — 43,560 square feet — and converting your lot’s dimensions into acres takes about thirty seconds once you know the formula.

Aerial view of farmland parcels when calculating acreage

How Many Square Feet Are in an Acre?

One acre = 43,560 square feet. The number dates back to the amount of land a yoke of oxen could plow in a day, but today it is just a fixed conversion factor: multiply or divide by 43,560 and you move between square feet and acres. For reference, it is also 4,840 square yards. This acreage reference lists the figure alongside the most common conversion mistakes.

The Acreage Formula

For any rectangular or square lot:

Acres = (Length in feet × Width in feet) ÷ 43,560

  1. Measure the lot’s length and width in feet (a long tape or measuring wheel works best).
  2. Multiply to get square feet.
  3. Divide by 43,560 to get acres.

Worked Example: A Rectangular Lot

A lot measures 200 feet by 250 feet. Multiply: 200 × 250 = 50,000 square feet. Divide: 50,000 ÷ 43,560 = 1.15 acres. That is the number a listing, a sod order, or a fence estimate will use.

Aerial view of a large field used to calculate acreage

Irregular Lots: Divide and Add

Most real lots are not perfect rectangles. Sketch the lot, divide it into rectangles and triangles, calculate each piece, and add them up — the same divide-and-conquer approach in our square footage guide. For a triangle, area = 0.5 × base × height.

Example: a lot splits into a 150×200-foot rectangle (30,000 sq ft) plus a triangle with a 150-foot base and 80-foot height (0.5 × 150 × 80 = 6,000 sq ft). Total: 36,000 sq ft ÷ 43,560 = 0.83 acres.

Top-down aerial view of land plots for acreage measurement

Acreage Conversion Table

1 acre equals Value
Square feet 43,560
Square yards 4,840
Square meters 4,046.86
Hectares 0.4047
Square miles 1/640 (0.00156)

For quick conversions between all of these, this acreage converter handles feet, yards, meters, and hectares in one place.

Visualizing an Acre

Numbers are abstract, so here is a picture: an American football field without the end zones covers about 48,000 square feet — roughly 1.1 acres. A square acre is about 208.7 feet on each side, a little shorter than a city block. If you can picture a football field, you can picture an acre.

From Acreage Back to Square Feet

Going the other direction is just multiplication: acres × 43,560 = square feet. A 2.5-acre lot is 108,900 square feet. Start from measured square footage with our calculate square feet guide, then convert up to acres whenever the project — sod, fencing, land listings — calls for it.

Planning a flooring or landscaping project?
Get help measuring your space and estimating materials.

Call (858) 399-8124

Further reading: This Old House yard and landscaping guides

Frequently Asked Questions

Related: how to calculate square yards

How do I calculate the acreage of my land?

Measure the length and width in feet, multiply to get square feet, then divide by 43,560. A 200×250-foot lot is 50,000 sq ft ÷ 43,560 = 1.15 acres.

How many square feet are in an acre?

Exactly 43,560 square feet — also 4,840 square yards or about 4,047 square meters.

How do I calculate acreage for an irregular-shaped lot?

Sketch the lot, split it into rectangles and triangles, calculate each piece (triangle = 0.5 × base × height), add them up, then divide the total square feet by 43,560.

How many acres is a 200×200 lot?

200 × 200 = 40,000 square feet; 40,000 ÷ 43,560 = 0.92 acres.

How do I convert square yards to acres?

Divide square yards by 4,840. A 9,680-square-yard lot is exactly 2 acres.

How big is an acre visually?

Picture a football field without the end zones — about 1.1 acres. A square acre measures roughly 208.7 feet on each side.

What is the difference between an acre and a hectare?

A hectare is larger: 1 hectare = 2.47 acres, or 10,000 square meters. Acres are standard in the US; hectares are standard in most of the rest of the world.

Do I measure to the fence line or the property line?

For true acreage, use the legal property boundaries from your plat or survey — fences are often set back from the actual line. For estimating sod or seed, the fence line is usually close enough.


Please follow and like us:
Scroll to Top