Acres Per Hour Calculator
This acres per hour calculator turns cutting width and ground speed into a work rate, then applies an efficiency factor so the number matches what you actually cover. The raw formula assumes you never overlap, turn or stop, and that's why it always flatters the machine.
Your result
Your work rate
1.67 acres an hour with a 60" width at 5 mph and 55% efficiency
The theoretical figure assumes no overlap, no turns and no stopping. Nobody ever hits it, which is why the realistic number is the one to plan with.
- What efficiency costs you
- 1.36 acres an hour lost to overlap, turning and stopping. Over an 8 hour day that is 10.9 acres you will not cover.
- Job time
- 2 acres at 1.67 acres an hour is 1 hr 12 min. At the theoretical rate it would be 40 min, which is the gap the efficiency factor exists to close.
- How this is worked out
- 5 ft × 5 mph ÷ 8.25 = 3.03 ac/hr, × 55% = 1.67 ac/hr
Calculate acres per hour
Width in feet times speed in mph, divided by 8.25. A 60 inch deck at 5 mph gives 3.03 acres an hour on paper, and about 1.67 in a real yard.
- Use the cutting width, not the machine width. A zero-turn with a 60 inch deck is wider than 60 inches overall, and the deck is what does the work.
- Use your real ground speed. Not the top speed on the spec sheet. Most operators cut several mph below what the machine can do, because quality falls apart above it.
- Pick an efficiency factor. This is the step every other calculator skips, and it's worth more than the other two combined.
- Plan with the realistic number. The theoretical one is useful only for comparing machines against each other.
Doubling your deck width doubles your rate. Doubling your speed does the same thing on paper, but in practice speed runs into cut quality and rough ground long before width does, which is why operators buy wider rather than drive faster.
The formula explained, and where the divisor comes from
Acres per hour equals width in feet times speed in mph times 5,280, all divided by 43,560. Those two constants collapse into a single divisor of 8.25.
The logic is simpler than it looks. Speed in mph times 5,280 gives you feet travelled in an hour. Multiply that by your cutting width in feet and you have square feet cut in an hour. Divide by 43,560, the number of square feet in an acre, and you have acres.
Because 43,560 divided by 5,280 is 8.25, you can skip both steps: width times speed divided by 8.25. That is the whole calculation, and it's why a 5 foot deck at 5 mph lands so close to 3 acres an hour before any allowance for reality.
Typical acres per hour by deck width
A 42 inch lawn tractor covers around 1.17 acres an hour in a residential yard. A 60 inch zero-turn does 1.67, and a 10 foot bush hog 5.15 in open field.
| Machine | Width | Theoretical | Open field (85%) | Residential (55%) |
|---|---|---|---|---|
| Push mower | 21" | 1.06 | 0.9 | 0.58 |
| Lawn tractor | 42" | 2.12 | 1.8 | 1.17 |
| Mid zero-turn | 48" | 2.42 | 2.06 | 1.33 |
| Large zero-turn | 60" | 3.03 | 2.58 | 1.67 |
| Commercial / small bush hog | 72" | 3.64 | 3.09 | 2 |
| 10 ft bush hog | 120" | 6.06 | 5.15 | 3.33 |
Read across any row and the cost of site conditions is obvious. The same machine covering the same ground does barely half as much in a yard full of obstacles as it does in an open field, and no change to the machine will fix that.
All of these assume 5 mph. If you cut at 4, scale every figure down by a fifth. If you cut at 6, scale up by a fifth. The relationship is linear, so the arithmetic stays easy.
Width behaves the same way, which is worth knowing when you're comparing machines. Going from a 42 inch deck to a 60 is a 43% jump in output at the same speed, and it costs you nothing in cut quality. Going 43% faster on the 42 would cost you plenty.
Efficiency factor: why you never hit theoretical output
Expect 85% of theoretical in open field and about 55% in a residential yard. Tight sites with gates and heavy trimming fall to 40%.
Three things take the difference. Overlap is the quiet one: nobody drives a perfectly adjacent pass, so a few inches of every pass is ground you already cut, and on a 60 inch deck a 4 inch overlap is nearly 7% gone before anything else happens.
Turning is the big one. Every headland turn is time at zero productive width, and short passes mean more turns per acre. That is why a long thin field mows faster than a square one of the same size, and why small yards are so much worse than the raw acreage suggests.
| Conditions | Efficiency | What it looks like |
|---|---|---|
| Open field | 85% | Long straight passes, almost no obstacles |
| Large open lawn | 70% | Wide turns, a few trees to go round |
| Residential yard | 55% | Beds, trees and fences, constant turning |
| Tight or complex | 40% | Small sections, gates, heavy trimming |
The third factor is simply stopping: emptying a bag, moving a hose, talking to the customer. It's small on any one pass and substantial across a day, and it's the piece most people forget when they wonder why the job overran.
Bush hog and tractor work rates
A 10 foot bush hog at 5 mph covers about 5.15 acres an hour in open field, which is roughly 2 times what a 60 inch zero-turn manages on the same ground.
Rough ground changes the sum differently from obstacles. Brush, ruts and stumps make you slow down rather than turn more, so the honest adjustment is to drop the mph rather than the efficiency percentage. Cutting heavy brush at 3 mph instead of 5 costs you two fifths of your rate, and no efficiency figure captures that.
Implement width is also where the biggest gains live. Going from a 6 foot to a 10 foot cutter is a two thirds increase in output at the same speed, which is why acreage contractors chase width while residential operators chase maneuverability.
How long will your job take?
Divide acres by your realistic rate. Five acres at 2.58 acres an hour is about 1.9 hours on open ground, and 3 in a broken-up yard.
| Acres | 60" zero-turn, open | 60" zero-turn, residential | 10 ft bush hog, open |
|---|---|---|---|
| 1 | 0.4 hr | 0.6 hr | 0.2 hr |
| 2 | 0.8 hr | 1.2 hr | 0.4 hr |
| 5 | 1.9 hr | 3 hr | 1 hr |
| 10 | 3.9 hr | 6 hr | 1.9 hr |
Add travel, unloading and trimming on top of every figure here. Those aren't covered by the efficiency factor, which only accounts for time lost while the machine is running.
For quoting, that distinction matters. The mowing time is what this table gives you, and the rest of the job is what turns it into a price on the free lawn mowing cost calculator.
Plan a day rather than a job. Eight hours on the clock is rarely eight hours of cutting once you count loading, driving between sites and refuelling, so an operator covering 3.9 hours of mowing has probably filled a day by the time everything else is added.
That gap is where most schedules go wrong. Booking back to back off the raw mowing time is how a five-job day turns into a seven-hour overrun.
Acres per hour FAQ
How to calculate acres per hour?
Multiply cutting width in feet by ground speed in mph, then divide by 8.25. A 60 inch deck is 5 feet, so at 5 mph that is 3.03 acres an hour in theory. Multiply by an efficiency factor to get what you will really cover.
What is the formula for acres per hour?
Width in feet times speed in mph times 5,280, divided by 43,560. That simplifies to width times speed divided by 8.25. The 5,280 turns miles into feet and the 43,560 turns square feet into acres, so the divisor is just those two combined.
How many acres per hour can a 60 inch mower do?
About 1.67 acres an hour in a residential yard and 2.58 in open field, at 5 mph. The theoretical figure is 3.03, but overlap, turns and stopping mean nobody reaches it over a full day.
What is a realistic efficiency factor?
Around 85% for open field work with long straight passes, and 55% for a residential yard full of beds and trees. Tight sites with gates and heavy trimming drop to 40%. The tighter the site, the more of your hour goes into turning.
How many acres per hour with a bush hog?
A 10 foot bush hog at 5 mph covers about 5.15 acres an hour in open field, against a theoretical 6.06. Rough ground usually means slower speed rather than lower efficiency, so drop the mph rather than the percentage.
How long does it take to mow 5 acres?
About 1.9 hours with a 60 inch zero-turn on open ground, or 3 hours if it is broken up with trees and beds. A 10 foot bush hog does the same 5 acres in roughly 1 hours.
Why is my actual rate lower than the calculator says?
Because the raw formula assumes you never overlap a pass, never turn and never stop. In practice you overlap a few inches every pass, spend real time on headland turns, and stop to empty a bag or move a hose. That’s what the efficiency factor is for.
Does mowing faster always cover more ground?
Only up to a point. Cut quality falls off as speed rises, and on rough ground the machine starts bouncing, so you leave stragglers and end up going back over it. Most operators find their real limit well below the machine top speed.