Mulch & Soil Calculator

Cubic yards and bags of mulch, soil or compost.

How it’s calculated

Cubic feet = area (sq ft) × depth (in) ÷ 12 × (1 + waste%). Cubic yards = cubic feet ÷ 27. Bags = cubic feet ÷ bag size, rounded up.

Bag sizes vary (2 cu ft is common for mulch; soil is often 0.75–1.5 cu ft) — enter the size printed on your bag.

Worked examples

10×10 ft bed at 3 in: 100 × 3 ÷ 12 = 25 cu ft = 0.93 cu yd; +5% = 26.25 cu ft → 14 bags of 2 cu ft.

Round bed, 8 ft diameter, 2 in: area = 3.1416 × 4² = 50.3 sq ft; × 2 ÷ 12 = 8.4 cu ft → 5 bags at 2 cu ft (with 5%).

Waste factor

Mulch and soil settle and compact after spreading. A 5–10% cushion is a reasonable rule of thumb (not a manufacturer figure); use more for loose, fluffy material.

FAQ