Mulch Calculator
Work out how much mulch to order from your bed size and how deep you want it. Get the volume in cubic yards for bulk delivery and in cubic feet, plus the number of bags — so you can compare bulk against bags before you buy.
For odd-shaped beds, estimate the area however is easiest.
2 ft³ is the common bag — confirm the volume printed on yours.
Advanced: price
Formula & how it works
Volume = bed area × (depth ÷ 12) cubic feet. Cubic yards = cubic feet ÷ 27.
Bags = cubic feet ÷ bag volume, rounded up. A cubic yard is roughly 13.5 of the standard 2 ft³ bags.
Worked example
A 20 × 10 ft bed is 200 ft². At 3 in deep that's 200 × 0.25 = 50 ft³, or about 1.85 cubic yards — roughly 25 bags at 2 ft³ each. Since that's over a yard, bulk delivery would likely beat buying twenty-five bags.
Ordering mulch well
Depth is the dial
Because mulch is thin and wide, depth drives the volume far more than it feels like it should — going from 2 to 3 inches is a 50% jump in material. Two to three inches suppresses weeds and holds moisture for most beds, and a top-up over existing mulch often needs only an inch. Set the depth deliberately rather than eyeballing the pile.
Bulk versus bags
Bags win on convenience and for small beds; bulk wins on price once you're past about a cubic yard, which is only around thirteen or fourteen of the common bags. Watch the cubic-yard figure — when it climbs past one, it's usually worth a bulk quote, and you skip hauling and splitting open a stack of plastic bags.
Confirm the bag volume
Mulch bags aren't all the same: 2 ft³ is most common, but 1.5 and 3 ft³ show up too, and a smaller bag quietly raises your bag count. Check the volume printed on the bag and enter it, especially when you're comparing a per-bag price against bulk by the yard.