Mulch Calculator
Work out mulch volume for rectangular, circular or triangular beds in cubic yards, cubic metres and bags, and compare bagged mulch against a bulk delivery.
Volume = bed area × depth. At the depth you entered, one yd³ spreads over about 108 sq ft— the familiar rule that a cubic yard covers roughly 108 sq ft at 3 inches deep. Bagged mulch is quoted by loose volume and settles once spread. Estimates only; check your supplier's bag size before ordering.
What is the Mulch Calculator?
The ByteTools Mulch Calculator turns a garden bed and a spread depth into a volume you can order. Choose a rectangular, circular or triangular bed, enter its dimensions and the depth of mulch you want, and it returns cubic yards, cubic metres and cubic feet together with the number of bags at common bag sizes.
- Rectangular, circular and triangular beds
- Results in cubic yards, cubic metres and cubic feet
- Bag counts for 2 ft³, 3 ft³, 50 L and 70 L bags
- Bulk delivery cost from your price per yard or metre
- Shows the ground area one unit covers at your depth
- Imperial and metric, all offline in your browser
How to use the Mulch Calculator
- 1
Choose imperial or metric and pick the shape of your bed.
- 2
Enter the bed dimensions and the depth of mulch you want to lay.
- 3
Adjust the extra allowance if you want to account for settling.
- 4
Enter your supplier's bulk price to compare against bagged mulch.
- 5
Read the cubic yards or metres and the number of bags required.
About the Mulch Calculator
The ByteTools Mulch Calculator turns a garden bed and a spread depth into a volume you can order. Choose a rectangular, circular or triangular bed, enter its dimensions and the depth of mulch you want, and it returns cubic yards, cubic metres and cubic feet together with the number of bags at common bag sizes.
It also prices a bulk delivery at your supplier's rate per cubic yard or cubic metre, which is where the real saving usually is — bagged mulch costs several times more per unit volume once you are past a few beds. The tool shows how much ground one unit covers at your chosen depth, so you can sanity-check the order.
Everything is worked out in your browser with nothing uploaded. Bag volumes and shredded-material densities vary by supplier, so treat this as an estimate and check the bag size printed on the pack before you buy. The same maths works for bark chips, compost, wood chip and decorative aggregate — only the depth you want tends to change.
Frequently asked questions
How much area does a cubic yard of mulch cover?
A cubic yard is 27 cubic feet, so at the common 3-inch depth it covers about 108 square feet. At 2 inches it stretches to roughly 162 square feet, and at 4 inches it drops to about 81. The calculator shows this coverage figure for whatever depth you enter.
How many bags of mulch are in a cubic yard?
Bagged mulch is usually sold in 2 cubic foot bags, so a cubic yard takes 13.5 of them — in practice 14. Three-cubic-foot bags take 9 per yard. Above about two cubic yards a bulk delivery is normally much cheaper.
How deep should mulch be?
Two to three inches (about 5 to 7.5 cm) suits most beds, and up to four inches helps suppress persistent weeds. Going deeper than that can starve roots of air and hold too much moisture against stems, so keep mulch pulled back from trunks and crowns.
Should I order extra mulch?
Mulch is normally ordered flat, without a waste allowance, because it is spread rather than cut to fit. The extra-allowance field is set to zero by default; add a few percent if your beds are uneven or you expect the material to settle noticeably.
How is the volume calculated?
Volume is simply bed area multiplied by depth. Rectangular beds use length × width, circular beds use π × radius², and triangular beds use half of base × height. Everything is then converted into yards, metres and bag counts.
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