How to calculate cubic yards
cubic yards = (L × W × D in feet) ÷ 27
Example: 12 ft × 10 ft bed, 3 inches of mulch
- Convert depth to feet: 3\" ÷ 12 = 0.25 ft
- Multiply: 12 × 10 × 0.25 = 30 cubic feet
- Divide by 27: 30 ÷ 27 = 1.11 cubic yards
- Order: 1.25 yd (add ~10% for settling)
How to calculate board feet
board feet = (T × W × L) ÷ 12
T and W in inches, L in feet
A board foot is a volume unit equal to 144 cubic inches (1 ft × 1 ft × 1 inch). Standard 2×4×8 = (2 × 4 × 8) ÷ 12 = 5.33 bf. Use nominal dimensions for pricing, lumber is priced by nominal, even though actual dimensions are smaller (a '2×4' is really 1.5\" × 3.5\").
Material coverage guide (100 sq ft)
| Depth | Cubic yards | Cubic feet |
|---|---|---|
| 1" | 0.31 | 8.33 |
| 2" | 0.62 | 16.67 |
| 3" | 0.93 | 25.00 |
| 4" | 1.23 | 33.33 |
| 6" | 1.85 | 50.00 |
| 8" | 2.47 | 66.67 |
| 12" | 3.70 | 100.00 |
Common material weights (lbs per cubic yard)
| Material | Lbs / yd³ | Tons / yd³ | Notes |
|---|---|---|---|
| Concrete (mixed) | 4,050 | 2.02 | ~2 tons per cubic yard; poured foundations, slabs |
| Gravel (dry) | 2,800 | 1.40 | Road base, drainage, driveways |
| Gravel (wet) | 3,375 | 1.69 | Heavier when saturated |
| Sand (dry) | 2,700 | 1.35 | Paver base, sandbox |
| Topsoil (dry) | 2,000 | 1.00 | Landscaping, lawns |
| Topsoil (wet) | 3,240 | 1.62 | After rain; heavier to haul |
| Mulch (wood) | 500 | 0.25 | Gardens, playgrounds; covers ~100 sq ft at 3" deep |
| Compost | 1,100 | 0.55 | Garden amendment |
| Asphalt (compacted) | 3,960 | 1.98 | Pavement, driveways |
| Crushed stone | 2,700 | 1.35 | #57 stone, drainage |
Standard lumber board feet
| Nominal size | Board feet |
|---|---|
| 2×4×8 | 5.33 bf |
| 2×4×10 | 6.67 bf |
| 2×4×12 | 8.00 bf |
| 2×6×8 | 8.00 bf |
| 2×6×12 | 12.00 bf |
| 2×8×12 | 16.00 bf |
| 2×10×12 | 20.00 bf |
| 4×4×8 | 10.67 bf |
| 1×6×8 | 4.00 bf |
How to order materials by the cubic yard without overpaying
Most bulk landscape and construction materials are sold by the cubic yard. The number you punch into the calculator is rarely the number you order, though. Three adjustments turn raw volume into a practical purchase order:
- Add for compaction. Mulch, topsoil, and gravel settle by 5-20% over the first few weeks. For a 4-inch mulch bed, plan to start at 5 inches loose, knowing it'll settle to 4 once it rains and gets walked on.
- Add for spillage and waste. Any project involving a wheelbarrow or shovel loses 5-10% to slop and overshoot. Concrete pours especially benefit from a small overage — running short mid-pour ruins the slab.
- Round up to the nearest delivery unit. Some suppliers sell in 1-yard increments, others in quarter-yard. There's no point ordering 2.13 cubic yards if the truck only delivers whole yards.
Most contractors use a rule of thumb: add 10% for soil and mulch, 15% for gravel and stone, 5% for concrete. Concrete has a tighter tolerance because the surcharge for return loads is high if you over-order, but stone and soil can be reused or dispersed easily if you're left with extra.
What a dump truck of material actually weighs
Volume is half the story. Weight matters when arranging delivery, planning driveway access, and figuring out whether your local supplier's truck can even bring you what you ordered.
| Truck type | Cubic yards (volume) | Max weight payload |
|---|---|---|
| Pickup truck (half-ton) | 0.5-1 yd | 1,000 lbs |
| Pickup truck (3/4-ton) | 1-2 yd | 2,000 lbs |
| Single-axle dump truck | 5-7 yd | 14,000 lbs |
| Tandem (tri-axle) dump truck | 10-12 yd | 23,000-26,000 lbs |
| Semi-trailer (live-bottom) | 15-20 yd | 40,000 lbs |
Practical implications: a half-ton pickup loaded with 2 yards of crushed stone (~5,400 lbs) is dangerously overweight and illegal to drive on most roads. The supplier may legally refuse to load you that heavy. Conversely, a single-axle dump truck full of mulch (1,000 lbs/yd) is far below its weight limit and can usually deliver an oversized "heaped" load — get a quote for a heaped vs struck load.
If your driveway is narrow, gated, or has overhead branches, ask about delivery vehicle size before ordering. A 12-yard tri-axle won't fit down a 7-foot-wide private drive, and turning around a loaded truck on a residential lot can damage lawns and sewers. Many suppliers offer dump-trailer rentals as an alternative for tight access sites.
Frequently asked questions
How do I calculate cubic yards?
Multiply length × width × depth (all in feet), then divide by 27 (since 1 cubic yard = 27 cubic feet). Formula: cubic yards = (L × W × D in ft) ÷ 27. Example: a 12 ft × 10 ft area with 3 inches (0.25 ft) of mulch = 12 × 10 × 0.25 = 30 cubic feet ÷ 27 = 1.11 cubic yards. Order slightly more than calculated (add 5–10%) to account for settling and irregular fill.
How do I calculate board feet?
Board feet = (thickness in inches × width in inches × length in feet) ÷ 12. A standard 2×4×8 = (2 × 4 × 8) ÷ 12 = 5.33 board feet. For nominal lumber, use actual dimensions for accuracy, a '2×4' is actually 1.5" × 3.5", so real board feet = (1.5 × 3.5 × 8) ÷ 12 = 3.5 bf. Most lumber is priced by nominal board feet, not actual.
How much mulch do I need?
Measure the area in square feet, then multiply by desired depth in feet. Most gardens use 2–3 inches (0.17–0.25 ft). For a 100 sq ft bed at 3" deep: 100 × 0.25 = 25 cubic feet = 0.93 cubic yards. Order 1 cubic yard. One cubic yard of mulch covers about 100 sq ft at 3" or 150 sq ft at 2". Bagged mulch: 1 cubic yard ≈ 13.5 bags (2 cu ft each).
How much concrete do I need for a slab?
Calculate cubic yards: (length × width × thickness in ft) ÷ 27. A 10×10 ft slab at 4" (0.33 ft) thick = 10 × 10 × 0.33 ÷ 27 = 1.23 cubic yards. Concrete is sold by the cubic yard (~$125–150 delivered). Order 10% extra to account for uneven ground and spillage. For small jobs (<0.5 yd), bagged concrete is more economical: one 60 lb bag = 0.45 cu ft, so a 10×10×4" slab takes ~74 bags.
How much gravel do I need for a driveway?
For a gravel driveway, plan 4–6" of base gravel plus 2–3" of surface stone. A 12×50 ft driveway at 4" (0.33 ft) deep = 12 × 50 × 0.33 ÷ 27 = 7.4 cubic yards of base, plus 3.7 yards of surface stone. At roughly $30–50/yd for gravel, budget $450–750 for materials (plus delivery $75–200). One cubic yard weighs ~1.4 tons (wet ~1.7 tons).
What's the difference between cubic feet and cubic yards?
A cubic yard is 27 cubic feet (3 ft × 3 ft × 3 ft = 27 cu ft). Landscape and construction materials like mulch, gravel, and concrete are typically sold in cubic yards. Smaller bagged materials are often in cubic feet: 2 cu ft, 3 cu ft bags. To convert: divide cubic feet by 27 to get cubic yards, or multiply cubic yards by 27 to get cubic feet.
How many tons are in a cubic yard?
It depends on the material density. Common weights per cubic yard: concrete ~2 tons, gravel (dry) ~1.4 tons, gravel (wet) ~1.7 tons, topsoil (dry) ~1 ton, sand ~1.35 tons, mulch ~0.25 tons. A dump truck typically holds 10–15 cubic yards (20+ tons). Always ask your supplier for the specific material density, it varies by region and moisture content.
How do I measure an irregular area?
Break it into regular shapes (rectangles, triangles, circles), calculate each separately, then add them up. For L-shaped areas: calculate two rectangles. For round or curved areas: use π × r² for circles. For irregular perimeters, approximate with rectangles or measure the longest and widest dimensions and average them. Order 10–15% extra material for irregular projects.
What is a board foot?
A board foot is a unit of lumber volume equal to 144 cubic inches, 1 ft × 1 ft × 1 inch. Formula: bf = (T × W × L) ÷ 12 where T and W are in inches and L is in feet. Lumber yards price by board feet for hardwoods and premium lumber. A 12-ft-long 2×6 board = 12 board feet. Dimensional lumber (2×4s, 2×6s) is usually priced per piece, not per board foot.
How many cubic feet are in a gallon?
1 US gallon = 0.134 cubic feet (or 1 cubic foot = 7.48 gallons). 1 cubic yard = 202 gallons. These conversions matter for ponds, aquariums, and fuel storage. Metric: 1 cubic meter = 264 gallons = 1,000 liters. Our volume converter handles all these conversions instantly.