Lawn
Lawn Area Calculator
Almost every other lawn number depends on this one. Break your yard into simple shapes, subtract the parts that aren't grass, and get a square footage you can use for seed, fertilizer, and quotes.
Updated
Measure the whole space
Add a section for each part of the yard. Odd shapes are easiest as two or three simple ones, a curve can usually be approximated by a rectangle through its middle.
Area = length × width
Subtract what isn't grass
Everything you measured above that is not turf. Leave blank what does not apply.
Add your measurements to see your lawn area.
Measuring without a tape
Pacing is accurate enough for lawn work. Measure your stride over a known 50 ft run first, most adults land between 2.5 and 3 ft per pace, then count paces. A calibrated pace is usually within 5% over yard-sized distances, which is fine for seed, fertilizer, and mulch. Use a tape for sod, where running short means a second delivery fee.
How this is calculated
Break it into shapes
No real yard is a rectangle, but every real yard is a handful of rectangles, triangles, and circles added together with a few subtracted. That is the entire method, and it is more accurate than any single overall measurement.
Measure each section separately, add the grass sections, and subtract the house footprint, driveway, patio, and planting beds. What is left is the area you actually seed, feed, and pay someone to mow.
lawn area = Σ(grass sections) − Σ(beds, drives, structures)
| Shape | Formula |
|---|---|
| Rectangle | length × width |
| Square | side² |
| Circle | π × (diameter ÷ 2)² |
| Triangle | ½ × base × height |
| Trapezoid | ½ × (side A + side B) × height |
| Oval | π × (long axis ÷ 2) × (short axis ÷ 2) |
Measuring without a tape
Pacing is accurate enough for lawn work. Measure your own stride over a known 50 ft distance, then count paces. Most adults land between 2.5 and 3 ft per pace, and a calibrated pace is usually within 5% over yard-sized distances.
For a whole property, a satellite measuring tool gives a good check figure. It will include beds and hardscape, so treat it as an upper bound and subtract from there.
Round up slightly rather than down. Running 5% over on seed costs a few dollars; running short means a second trip and a visible seam where you ran out.
Converting units
An acre is 43,560 square feet, a number worth memorising if you deal with larger properties. A typical US suburban lawn runs 5,000 to 10,000 sq ft, so somewhere between an eighth and a quarter acre.
A square yard is 9 square feet, which matters when a supplier quotes sod or turf by the square yard rather than the square foot.
Worked example
A typical suburban lot
A 70 ft × 110 ft lot with a 40 ft × 30 ft house, a 20 ft × 30 ft driveway, and about 250 sq ft of planting beds.
- Whole lot
- 70 × 110 = 7,700 sq ft
- Less house
- 40 × 30 = 1,200 sq ft
- Less driveway
- 20 × 30 = 600 sq ft
- Less beds
- 250 sq ft
- Lawn area
- 7,700 − 2,050 = 5,650 sq ft
About 5,650 sq ft of actual turf, or 0.13 acres. That is the number to use for seed and fertilizer, using the 7,700 sq ft lot size would overbuy by more than a third.
Frequently asked questions
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