Lawn Size Calculator
Measure your lawn to get accurate equipment recommendations and product quantities. Essential for using other calculators effectively.
Tool inputs
2 minutesUnderstanding lawn measurement
The map you draw on is georeferenced. Each pixel maps to a known ground distance, so the polygon you trace converts directly to square footage without a tape measure.
Drop a pin at your address, zoom in until the lawn fills most of the screen, and trace the boundary by clicking corners. The tool computes the area of the resulting polygon using the same spherical-geometry math the U.S. Geological Survey uses for parcel measurement.
Accuracy under good conditions is within ±3% of a tape-measured value — close enough for fertilizer rates, seed-bag math, sod orders, and irrigation zones. The two things that hurt accuracy are tree canopy hiding turf edges and very small lawns under 500 sq ft, where one pixel of error matters more.
Most lawn-care math is per-1000-sq-ft. Get the size wrong and every downstream rate is wrong by the same percentage.
| Calculation | Why size matters | Cost of a 20% error |
|---|---|---|
| Fertilizer rate | Pounds of N per 1000 sq ft × your size = how much to apply | Burn the lawn or under-feed it; one bag wasted |
| Seed bag math | Pounds of seed per 1000 sq ft × size = bags to buy | Bare patches or $40+ in unused seed |
| Sod order | Pallets cover a fixed sq ft (usually 450) | Short by half a pallet on delivery day |
| Watering depth | Gallons to deliver 1 inch = 623 × size in 1000s | Runoff or drought stress; wasted water bill |
| Pre-emergent herbicide | Coverage ratings on the bag are per 1000 sq ft | Crabgrass breakthrough or off-label rates |
Once you have an accurate size, plug it into the fertilizer, seeding, watering, and herbicide-timing calculators on this site.
- Including the driveway, sidewalk, or mulch beds. Trace the turf only — that's what gets fertilizer and water.
- Tracing at low zoom. The further out you are, the bigger one pixel of slop becomes. Zoom until you can see individual lawn corners.
- Forgetting backyards or detached side strips. Most homes have at least two disconnected turf areas. Use the multi-polygon mode.
- Measuring during snow cover or after a fresh mulch top-up. Both hide turf edges. Wait for clear satellite imagery.
- Trusting a county assessor's "lot size." That number includes the house, drive, deck, beds, and any pool — usually 30–60% larger than your actual lawn.
- After hardscape changes — new patio, walkway, expanded driveway, removed beds. Measure once, not before every fertilizer application.
- After a tree removal that reveals turf you couldn't see in satellite imagery before.
- When moving to a new house. The lot-size figure on Zillow or your tax record is not your lawn size.
- When a sod, irrigation, or landscaping pro quotes off a size that doesn't match yours — measurement disputes are easier to settle with a polygon screenshot.
For lawns over 1000 sq ft, satellite measurement is faster, more accurate, and lets you remeasure later without re-walking the property. The polygon approach handles irregular shapes (curved beds, kidney-shaped backyards) that a tape measure has to approximate as rectangles.
For tiny urban lots under 500 sq ft, a tape measure is competitive — pixel-level error matters when every square foot is 0.2% of the total. For everything in between, the satellite tool is the right default.
Why do I need to know my lawn size?
Knowing your lawn size is essential for accurately calculating how much fertilizer, seed, herbicide, and other lawn care products you need. It also helps determine the right equipment size and budget for maintenance.
What's the most accurate way to measure my lawn?
Our satellite map tool provides the most accurate measurements. Simply enter your address, then tap points around your lawn's border to draw your area. The calculator automatically computes the square footage.
Should I include my entire property or just the lawn?
Only measure the turfgrass areas that you actively maintain. Exclude driveways, patios, garden beds, and structures. Include only the areas where you mow, fertilize, and water grass.
How do I measure an irregular-shaped lawn?
Tap as many points as needed to trace around curves and irregular borders. The more points you add, the more accurate your measurement. You can also use the Undo button to remove the last point if you make a mistake.
What if my lawn has multiple disconnected areas?
Draw each area separately (front yard, back yard, side yard) and label them. The calculator automatically adds all areas together and shows you a breakdown of each section.