How big is your lawn, actually?
Find your house, click around the edge of the grass, and read the square footage. It is the number every robot mower is sold on, and the number most people guess wrong.
The free map database does not know every street, especially in newer US developments. If your address is not found, try just your ZIP code, or right-click your house in Google Maps, copy the two numbers it shows, and paste them here — that always works.
Open the satellite map
Loads only when you ask for it.
Separate patches of grass are traced one at a time and added up. Nothing you draw leaves your browser. The measurement is calculated on your device and never sent to us or stored on a server.
Why the number matters more than you think
Every robot mower carries a maximum coverage rating, and that rating assumes conditions you probably do not have: dry grass, a daily schedule and a reasonably open shape. A lawn with a tree in the middle, a narrow passage to the back garden and a wet fortnight in June is meaningfully harder work than the figure on the box.
So take the number this tool gives you and add about 15%. Buy for that. A mower with headroom finishes earlier, runs fewer hours a week and keeps its battery longer. A mower bought exactly to its limit never quite catches up in peak growth — which is when people conclude the technology does not work.
What to include and what to leave out
- Include every piece of grass the mower will cut, even separated patches. Trace the first one, press Add another area, trace the next — the tool keeps a list and adds them up for you.
- Exclude flower beds, paths, patios, the driveway and anything the mower will be fenced out of.
- Do not include a neighbour's grass, however tempting the shape.
Two other ways to measure
If satellite imagery of your street is out of date, pace it out instead: walk the length and the width in normal steps, multiply by your stride length, and split an irregular lawn into rectangles you add together. It is less precise than tracing, and still far better than guessing.
Once you have your number, the mower matcher filters our 24 models on coverage and gradient, so anything that physically cannot handle your lawn never appears in the results.