How Many Square Feet in an Acre (and How to Measure One)

An acre is 43,560 square feet. That number is the answer to the search, but it is not the number you quote from. Customers say "I'm on half an acre," county records list lot size in acres, and your mowing and fertilizer rates are probably per 1,000 square feet. This guide gives you the conversions, shows what an acre looks like on the ground, and explains how to get from "half an acre" to a price.

The exact definition

The acre is defined in NIST Handbook 44 as 43,560 square feet, 160 square rods, or 10 square chains, and a square mile is 640 acres NIST Handbook 44, Appendix C. In metric terms, one acre is 4,046.856 square meters based on the international foot NIST Handbook 44, Appendix C.

You may run into old survey documents that mention a "survey acre." As of January 1, 2023, the U.S. survey foot is obsolete and superseded by the international foot of exactly 0.3048 meter for all applications NIST. The same NIST table lists a survey acre at 4,046.873 square meters NIST Handbook 44, Appendix C. That works out to about 0.016 square meters, or roughly a quarter of a square foot, per acre. It does not matter for a lawn quote.

Square feet in common fractions of an acre

Every row below is 43,560 multiplied by the fraction. These are the lot sizes customers actually say on the phone.

Acreage	Square feet	Square yards
1/10 acre	4,356	484
1/8 acre	5,445	605
1/5 acre	8,712	968
1/4 acre	10,890	1,210
1/3 acre	14,520	1,613
1/2 acre	21,780	2,420
3/4 acre	32,670	3,630
1 acre	43,560	4,840
2 acres	87,120	9,680
5 acres	217,800	24,200

To go the other way, divide square feet by 43,560. A 12,000 square foot lot is 0.28 acres. A 30,000 square foot lot is 0.69 acres.

What an acre looks like in feet

An acre can be any shape. NIST makes the point directly: an acre is not necessarily a square or rectangle, and if it is a square, each side is about 208.71 feet NIST Handbook 44, Appendix C.

A few shapes that each equal one acre (length × width = 43,560):

Shape	Dimensions
Square	208.7 ft × 208.7 ft
Long rectangle	66 ft × 660 ft (one chain by one furlong)
Wide suburban lot	100 ft × 435.6 ft
Deep rural strip	50 ft × 871.2 ft

The 66 × 660 rectangle is where the number comes from. NIST defines a furlong as 660 feet NIST Handbook 44, Appendix C, and a Gunter's chain is 66 feet, so one chain by one furlong is 43,560 square feet.

For a sense of scale, a quarter-acre lot is about 104 feet on a side if square. A half-acre is about 148 feet on a side.

Lot acres vs. mowable square feet

This is where quotes go wrong. A customer's "half acre" is the parcel size. It includes the house, driveway, patio, beds, and trees. None of that gets mowed.

Survey data shows how big the gap is. Angi's analysis of Zillow single-family sales put state average lot sizes between 7,405 square feet in Nevada and 78,408 square feet in Vermont 24/7 Wall St., citing Angi's 2022 Lot Size Index. But a 2026 sample of 3,034 lawns that homeowners traced on satellite imagery had a median of just 3,044 square feet, and 62.7% were under 5,000 square feet What Grass Is This. Those are different samples, so do not subtract one from the other. The point is that turf is usually a fraction of the lot.

For lot data by state and what it means for your service area, see our guide to average lot and lawn size by state.

The practical rule: never price from lot acreage. Measure the turf. Our free Lawn Size Calculator lets you trace the grass from satellite imagery and get square feet and acres. If you want the manual method, our guide to measuring the square footage of a yard walks through it.

How to measure an acre in the field

If you cannot use imagery, there are three workable methods.

1. Measuring wheel or tape for rectangles. Measure length and width, multiply, divide by 43,560. A 120 × 180 ft backyard is 21,600 square feet, or 0.50 acres.

2. Break irregular yards into shapes. Split the yard into rectangles, triangles (½ × base × height), and circles (3.14 × radius²). Add them up. Subtract the footprint of beds and patios inside the area.

3. Pace it off for a rough number. Learn your stride length over 100 measured feet, then pace the edges. This is fine for "is it a half acre or a full acre," not for a final quote.

From satellite imagery. Trace the outline on an aerial map. This is the fastest way to measure a large or odd-shaped property and the only way to quote before you drive out. Our guide to measuring a lawn from satellite covers accuracy and what to exclude. If you already use Google Earth, see our Google Earth measure tool guide.

Converting product rates: per acre vs. per 1,000 sq ft

Seed, fertilizer, and lime labels switch between "per acre" and "per 1,000 square feet." The conversion factor is 43.56 (43,560 ÷ 1,000).

University of Arkansas Extension gives the method: to convert pounds per acre to pounds per 1,000 square feet, divide by 43.56, so 100 pounds per acre becomes about 2.3 pounds per 1,000 square feet, and 5,000 pounds of lime per acre becomes 115 pounds per 1,000 square feet University of Arkansas Cooperative Extension, FSA3110. To go from per-1,000 to per-acre, multiply by 43.56.

Label rate per 1,000 sq ft	Equivalent per acre
0.5 lb	21.8 lb
1 lb	43.6 lb
3 lb	130.7 lb
5 lb	217.8 lb

How acreage turns into a price

Published mowing prices by acreage give you a sanity check. These are per-visit ranges:

Lawn size	Housecall Pro	Jobber
1/4 acre	$45–$85	$25–$60
1/2 acre	$50–$100	$50–$75
1 acre	$60–$150	$150–$200
2 acres	$100–$260	—
5 acres	$200–$590	$450–$650

Sources: Housecall Pro, Jobber.

Notice that the price per acre falls as the property grows. Jobber's 5-acre range works out to $90–$130 per acre, below its 1-acre range of $150–$200 Jobber. Setup, drive time, and trimming are spread across more turf, and bigger properties justify bigger mowers.

Jobber also lists $0.01 to $0.06 per square foot for standard mowing Jobber. That is $10 to $60 per 1,000 square feet, or $436 to $2,614 per acre if applied flat, which is why nobody prices a full acre on a small-lawn rate.

A worked example. A customer says they have "about half an acre." You trace the turf and get 14,000 square feet, which is 0.32 acres, not 0.5. At $5 per 1,000 square feet with a $50 minimum, the cut is 14 × $5 = $70. If you had priced the full 21,780 square feet, you would have quoted $109 and likely lost the job to someone who measured.

Run your own rate sheet through our Mowing Price Calculator, and see how much to charge per 1,000 sq ft for how to set the rate itself.

Quick reference

• 1 acre = 43,560 sq ft = 4,840 sq yd ≈ 4,047 m²
• Square feet ÷ 43,560 = acres
• Acres × 43,560 = square feet
• Per-acre rate ÷ 43.56 = per-1,000-sq-ft rate
• 1 hectare ≈ 2.471 acres NIST Handbook 44, Appendix C

Sources

• NIST Handbook 44 (2023), Appendix C – General Tables of Units of Measurement
• NIST – U.S. Survey Foot
• University of Arkansas Cooperative Extension – FSA3110 Seeding and Fertilization Rate Calibration
• Housecall Pro – Lawn Mowing Cost & Prices
• Jobber – How Much to Charge for Lawn Mowing
• 24/7 Wall St. – How Much Land People Live on in Every State (Angi 2022 Lot Size Index data)
• What Grass Is This – Average Lawn Size by State (2026)