Mulch Calculator
Estimate bulk cubic yards or bag count from bed area and mulch depth without assuming one universal bag size.
How the mulch calculation works
Convert your mulch depth from inches to feet, multiply by the bed area to get cubic feet, then divide by 27 for cubic yards.
cubic yards = area (ft²) × depth (ft) ÷ 27
For bags, the calculator divides the waste-adjusted cubic feet by the bag volume printed on the product label and rounds up to a whole bag.
Example
A 20 ft × 10 ft bed at 3 in deep is 50 ft³, or about 1.85 yd³ before extra material. With 5% extra, that becomes about 52.5 ft³ or 1.94 yd³.
Why we do not assume a bag size
Mulch bag volume varies by product and retailer. Enter the cubic-foot volume printed on the exact bag you plan to buy. This avoids false precision and makes the result useful across brands.
Before buying mulch
Confirm whether you are ordering bulk material or bags. For bags, use the exact cubic-foot volume printed on the product rather than a generic bag size. For bulk orders, ask the supplier how they sell and round quantities so the calculator output can be matched to a real order.