Mowing time calculator
How long your lawn takes to mow for a given deck width and speed, and how much time that adds up to over a season.
How it works
Area covered per hour = deck width × speed × efficiency. Efficiency allows for overlap, turns and trimming, usually 70–85%. A 21-inch walk-behind at 3 mph covers about 27,700 sq ft an hour at 100%, or about 20,800 at 75%.
Quick reference
| 21 in push mower | 3 mph |
| 30 in walk-behind | 3.5 mph |
| 42 in lawn tractor | 5 mph |
| 54 in zero-turn | 7 mph |
Typical working speeds. Mowing on slopes and wet grass is slower.
Questions
Is a riding mower safer?
Not by default. Riding mowers have a higher share of hospital admissions in NEISS data, often from rollovers. Children should never ride along.
Injury data for these tools
Lawn mowers (walk-behind & unspecified)Laceration68,019
Riding mowers & garden tractorsFracture16,479ER visits in 2025
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