Mulch Calculator — Bags or Cubic Yards
Gives you bags and cubic yards side by side, so you can see which way is cheaper before you order. Add a section for each bed.
Take this list to the store
We'll email the quantities above, what you typed in, and a link that reopens this calculator already filled in — so you can adjust it on your phone in the aisle.
How to work it out
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Measure each bed separately
Beds are rarely one rectangle. Measure each straight run and add a section for it — a long border, a square around a tree, a strip along the drive. Curved beds are close enough if you take an average width.
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Choose the depth before the volume
Three inches is the standard for established beds. Two is enough for annual top-ups over existing mulch. Four is for heavy weed suppression on a new bed. Depth drives the entire order, so decide it first.
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Compare bags against bulk
The crossover is usually around two cubic yards, or roughly 27 bags. Below that, bags are easier and often cheaper once delivery is counted. Above it, bulk is dramatically cheaper — put both prices in and the calculator will tell you.
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Order slightly over
Mulch settles and beds are never quite the shape you measured. Half a yard extra, or a few spare bags, is better than stopping a job at four in the afternoon one bag short.
Mulch by bed size and depth
Cubic yards, with 2 cu ft bags in brackets.
| Bed area | 2 in. deep | 3 in. deep | 4 in. deep |
|---|---|---|---|
| 100 sq ft | 0.62 cu yd (9 bags) | 0.93 cu yd (13 bags) | 1.23 cu yd (17 bags) |
| 200 sq ft | 1.23 cu yd (17 bags) | 1.85 cu yd (25 bags) | 2.47 cu yd (34 bags) |
| 300 sq ft | 1.85 cu yd (25 bags) | 2.78 cu yd (38 bags) | 3.70 cu yd (50 bags) |
| 500 sq ft | 3.09 cu yd (42 bags) | 4.63 cu yd (63 bags) | 6.17 cu yd (84 bags) |
| 750 sq ft | 4.63 cu yd (63 bags) | 6.94 cu yd (94 bags) | 9.26 cu yd (125 bags) |
| 1000 sq ft | 6.17 cu yd (84 bags) | 9.26 cu yd (125 bags) | 12.35 cu yd (167 bags) |
| 1500 sq ft | 9.26 cu yd (125 bags) | 13.89 cu yd (188 bags) | 18.52 cu yd (250 bags) |
| 2000 sq ft | 12.35 cu yd (167 bags) | 18.52 cu yd (250 bags) | 24.69 cu yd (334 bags) |
One cubic yard covers about 160 sq ft at 2 in., 108 sq ft at 3 in., or 81 sq ft at 4 in.
How deep to go
| Situation | Depth | Why |
|---|---|---|
| Topping up an existing bed | 1–2 in. | Rake the old mulch first, then top up to about 3 in. total. |
| Established shrub bed | 3 in. | Suppresses most weeds without starving roots of air. |
| New bed, heavy weeds | 4 in. | Put cardboard down first and the weeds rarely come back. |
| Around a tree trunk | 3 in., none touching | Mulch piled against bark rots it. Leave a clear ring. |
| Playground or path | 6–12 in. | Safety surfacing is a different job with its own standards. |
More than 4 in. on a planting bed does more harm than good — roots need air as much as they need moisture.
How much mulch for 1,000 square feet?
At the standard 3 in. depth, 1,000 sq ft needs 250 cubic feet — that is 9.3 cubic yards, or 125 bags of 2 cu ft.
At that size bulk is obviously the answer. A hundred and twenty-five bags is four car loads and an afternoon of opening them; nine yards arrives on one truck for considerably less money.
When bulk becomes cheaper than bags
The crossover is around two cubic yards, or 27 bags.
Below that, bagged mulch usually wins: no delivery fee, you can carry it in stages, and leftovers stack in the garage. Above it, bulk is often half the price per yard even after delivery, and dumping one pile beats opening fifty bags.
Bulk has one catch worth knowing — it arrives as a pile on your driveway and it is your problem until it is moved. Nine yards is a real weekend's work with a wheelbarrow.
Do not pile it against trunks and stems
The volcano of mulch heaped around a tree trunk is the most common mulching mistake in America, and it kills trees slowly. Bark held permanently damp rots, and roots grow up into the mulch instead of down into the soil.
Keep a clear ring of two or three inches around every trunk and stem. Mulch belongs on the soil, not against the plant.
Which mulch to buy
- Shredded hardwood — knits together and stays put on slopes. The default for most beds.
- Bark nuggets — last longer, but float away in heavy rain and on any slope.
- Pine straw — light, acidic, excellent around azaleas and rhododendrons.
- Dyed mulch — color holds about a season. Usually ground pallet wood rather than bark.
- Rubber — never breaks down, adds nothing to the soil, and is hard to remove later. Fine for play areas, poor for beds.
How this is worked out
No black box — here is the arithmetic the calculator runs, so you can check it against your own numbers.
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area = length × width, summed over every bedEach section is added, so several beds order together. -
volume = area × depth ÷ 12Depth is in inches, area in square feet, so dividing by 12 gives cubic feet. -
bags = volume ÷ bag size, rounded upThe standard bag is 2 cu ft. -
cubic yards = volume ÷ 27A cubic yard is 3 × 3 × 3 ft. Bulk is always sold this way. -
bulk cost rounds to the nearest half yardMost suppliers will not split finer than that.
Common questions
How many bags of mulch in a cubic yard?
Thirteen and a half bags of the standard 2 cu ft size, since a cubic yard is 27 cubic feet. At 3 cu ft a bag it is nine bags.
How much does a cubic yard of mulch cover?
About 160 sq ft at 2 in. deep, 108 sq ft at 3 in., or 81 sq ft at 4 in. Depth changes the answer far more than people expect.
How deep should mulch be?
Three inches for an established bed. Two inches when topping up over existing mulch, four when you are smothering heavy weeds on a new bed. Deeper than four starts to starve roots of air.
Is bulk mulch cheaper than bags?
Above about two cubic yards, almost always — often half the price per yard even with delivery. Below that, bags usually win once you count the delivery fee, and they are far easier to handle.
When is the best time to mulch?
Mid to late spring, once the soil has warmed. Mulching too early keeps the ground cold and slows everything down. A lighter autumn application helps insulate roots over winter.
Should I remove the old mulch first?
Usually not. Rake it to break up any crust and top up to about 3 in. total. Only strip it out if it has matted into a water-shedding layer or is growing fungus.
Do I need landscape fabric underneath?
Rarely, and it often causes problems. Weeds root in the mulch on top of it, and the fabric stops organic matter reaching the soil. Plain cardboard under a new bed works better and rots away harmlessly.
How much mulch for a 10x10 bed?
One hundred square feet at 3 in. is 25 cubic feet — about 13 bags, or just under a cubic yard. Bags are the easier choice at this size.
Where these figures come from
Every figure below is traceable. How we check the numbers explains how they are verified, and the coverage reference collects them all in one place.
- University extension landscape guidance — recommended mulch depth and the clearance needed around trunks
- Mulch and Soil Council product standards — bag volumes and material descriptions
- Supplier bulk conversion tables — the coverage a cubic yard gives at each depth
Think a number here is wrong? Tell us — we check every report, correct the page, and date the change. Last checked September 11, 2026.