Gravel & Mulch Calculator
Volume = area × depth
How Gravel and Mulch Volume Calculations Work
Bulk landscaping materials are ordered by the cubic yard. Volume in cubic feet = area (sq ft) × depth (ft). Convert depth from inches: 3 inches = 3 ÷ 12 = 0.25 ft. A 12 ft × 12 ft garden bed (144 sq ft) mulched 3 inches deep needs 144 × 0.25 = 36 cubic feet. Divide by 27 to get cubic yards: 36 ÷ 27 = 1.33 yd³.
Weight in tons depends on material density. Gravel weighs roughly 1.4 tons per cubic yard; mulch about 0.5 tons; sand 1.3 tons; topsoil 1.1 tons. The 1.33 yd³ of mulch weighs 1.33 × 0.5 ≈ 0.67 tons. Gravel for the same volume would weigh nearly 1.9 tons — delivery trucks have weight limits, so cubic yards and tons both matter for ordering.
Recommended depths vary by material. Mulch beds use 2–4 inches (renew every 1–2 years). Gravel driveways need 4–6 inches of base plus 2 inches of surface stone. Playground mulch should be 6–12 inches for fall protection per safety guidelines. Topsoil for new lawns: 4–6 inches tilled into existing soil.
Compacted materials settle 10–15% after rain and traffic. Round up orders slightly. One cubic yard covers roughly 108 sq ft at 3 inches deep, or 81 sq ft at 4 inches. Bagged mulch (2 cu ft bags) is economical for small beds; bulk delivery saves money above ~2 cubic yards. Landscape fabric beneath gravel paths suppresses weeds without affecting drainage when properly pinned and overlapped six inches at seams.
| Area | Depth | Cubic Yards |
|---|---|---|
| 144 sq ft (12×12) | 3 in mulch | 1.33 yd³ |
| 500 sq ft driveway | 4 in gravel | 6.17 yd³ |
| 200 sq ft bed | 2 in mulch | 1.23 yd³ |
| 1,000 sq ft yard | 3 in topsoil | 9.26 yd³ |
Select gravel, mulch, sand, or topsoil, then enter area and depth for cubic feet, cubic yards, and tonnage. Use the square footage calculator to measure bed dimensions first.
Examples
| Example | Result |
|---|---|
| 12×12 ft bed, 3 in mulch | 36 cu ft, 1.33 yd³, 0.67 tons |
| 500 sq ft driveway, 4 in gravel | 166.7 cu ft, 6.17 yd³, 8.6 tons |
| 200 sq ft bed, 2 in mulch | 33.3 cu ft, 1.23 yd³ |
| 300 sq ft path, 3 in gravel | 75 cu ft, 2.78 yd³, 3.9 tons |
| 1,000 sq ft lawn, 4 in topsoil | 333 cu ft, 12.3 yd³ |
| 80 sq ft playground, 6 in mulch | 40 cu ft, 1.48 yd³ |
| 400 sq ft patio base, 4 in sand | 133 cu ft, 4.94 yd³ |
Frequently asked questions
Apply 2–4 inches of mulch for garden beds. Thinner layers decompose quickly; deeper than 4 inches can suffocate plant roots.
A standard pickup holds roughly 1–1.5 cubic yards level with the bed sides. Heaped loads may carry more but risk overweight fines.
Gravel averages about 1.4 tons (2,800 lb) per cubic yard. Mulch is much lighter at roughly 0.5 tons per cubic yard.