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Deck width decides how far you walk
Updated
Deck width is the biggest lever on mowing time, and so on whether the battery lasts. On a quarter acre of grass, a 14 inch deck means about 59 minutes of mowing in our estimate. A 21 inch deck means about 38. The battery does not care how wide the deck is. It cares how long it has to run.
A quarter acre, four deck widths
| Deck | Fresh cut per pass | Feet walked | Distance | Minutes (estimate) |
|---|---|---|---|---|
| 14 in | 12 in | 10,890 ft | 2.1 miles | 59 min |
| 16 in | 14 in | 9,334 ft | 1.8 miles | 51 min |
| 19 in | 17 in | 7,687 ft | 1.5 miles | 42 min |
| 21 in | 19 in | 6,878 ft | 1.3 miles | 38 min |
- 14 inch deck59 minutes
- 16 inch deck51 minutes
- 19 inch deck42 minutes
- 21 inch deck38 minutes
A quarter acre is 10,890 sq ft. We assume a 2 inch overlap, 2.5 mph and 20 percent extra for turns and edges. Change any of those in the calculator.
The number on the listing is the deck, not always the cut
Read the spec table as well as the title. The WORX WG779 is sold as a 14 inch mower, and its Amazon spec table lists a 13 inch cutting width. The Greenworks 16 inch lists 15.67 inches. The Greenworks 21 inch lists 20.28. The gaps are small, but they all run the same way.
When narrow is right
Greenworks describes its 16 inch deck as lightweight and easier to move around small yards. That is the real case for a narrow mower. It weighs less, it fits through a garden gate, it turns in tight strips beside a path, and it takes less room in the shed. On a lawn of 3,000 sq ft, the gap between a 14 and a 21 inch deck is 6 minutes. On a quarter acre it is 21.
When wide is right
Once your lawn takes more than about half an hour with a small deck, a wider one pays back every week. University of Minnesota Extension notes that mowing takes more time than any other lawn care job. A 21 inch steel deck mower like the Greenworks 60V 21 in SP is 65 pounds, though, so past a small flat yard a wide push mower gets tiring. That is where self-propel comes in.
Work out your own lawn with the mowing time calculator, or compare all six picks on the roundup page.