Square Feet to Cubic Yards Calculator
Convert an area in square feet plus a spread depth into the cubic yards of material to order.
Reviewed by the ToolNestr Editorial Team — July 2026
How the square feet to cubic yards calculator works
Square feet measure area and cubic yards measure volume, so the two cannot be converted directly — you need a depth to bridge them. Once you know how thick the material will be spread, the volume in cubic feet is the area times the depth in feet, and dividing that by 27 (the number of cubic feet in a cubic yard) gives the order in cubic yards.
Because depth is usually given in inches, convert it to feet by dividing by 12. A 3-inch spread is 0.25 feet, a 2-inch spread is 0.167 feet, and so on. This is why the same area needs very different amounts of material at different depths: doubling the depth doubles the cubic yards. Adding a waste allowance — commonly around 10% for landscape materials that settle, spill, or grade unevenly — gives a realistic amount to actually order.
If your supplier sells by weight instead of volume, the tool multiplies the cubic yards by a typical material density in tons per cubic yard. Mulch is light at roughly half a ton per yard, topsoil around 1.1 tons, gravel and sand near 1.35 tons, and concrete about 2 tons. These are approximate — moisture and gradation shift them — so treat the tonnage as an estimate for ordering.
The 27 cubic-feet-per-cubic-yard conversion and typical bulk material densities follow standard landscape-supply and NRMCA aggregate reference figures.
Enter the area
Total square footage you are covering.
Set the depth
How thick the material is spread, in inches.
Order in yards
Get cubic yards, plus tons if selling by weight.
The formula explained
Cubic feet
= area × (depth⁄12). 300 sq ft at 3 in: 300 × 0.25 = 75 ft³.
Cubic yards
= ft³ ÷ 27 = 75 ÷ 27 = 2.78 yd³.
With waste
Add 10%: 2.78 × 1.10 = 3.06 yd³ to order.
Worked example
A 500 sq ft driveway getting 4 inches of gravel, 10% waste.
Use cases for the square feet to cubic yards calculator
Mulch and landscaping beds
Flower beds, tree rings, and playground surfacing all get ordered by the cubic yard. Converting a measured area and target depth into yards keeps you from over- or under-ordering mulch.
New lawn and garden soil
Topdressing a lawn or building raised garden beds requires knowing the topsoil volume in cubic yards, since bulk soil suppliers price and deliver by the yard, not the bag.
Driveway and path base
Gravel base layers under driveways, patios, and walkways need a specific compacted depth. This calculator converts that depth and area into the cubic yards of aggregate to order.
Fill and grading projects
Leveling a low spot in a yard or filling in after excavation both require estimating fill dirt or sand volume from a measured area and target fill depth.
Real-world context
Refreshing a mulch bed is one of the most frequent uses of this calculator. A 250 sq ft flower bed spread 2 inches deep needs 250 × (2/12) = 41.7 cubic feet, or 1.54 cubic yards — round up to 1.7 cubic yards with 10% waste, weighing under 0.85 tons, which is why most homeowners just order mulch by the yard rather than by weight for a project this size.
New lawn installations need far more material. A 1,000 sq ft yard getting 4 inches of topsoil needs 1,000 × (4/12) = 333.3 cubic feet, or 12.3 cubic yards — with 10% waste that climbs to 13.6 cubic yards, weighing nearly 15 tons at topsoil's typical 1.1 tons per cubic yard, enough that most suppliers will require multiple truck loads.
Driveway base prep shows how depth and waste both compound. An 800 sq ft gravel driveway base at 3 inches deep needs 800 × (3/12) = 200 cubic feet, or 7.4 cubic yards — with a more generous 15% waste allowance for compaction and an uneven subgrade, that becomes 8.5 cubic yards weighing about 11.5 tons, since gravel runs around 1.35 tons per cubic yard.
Common misconceptions
"I can convert square feet straight to cubic yards without knowing depth." Not possible. Square feet is a two-dimensional measurement and cubic yards is three-dimensional. Without a depth, there is no volume to calculate — depth is what turns a flat area into a quantity of material.
"A cubic yard of any material weighs about the same." Density varies enormously. A cubic yard of mulch weighs around 500-700 lb, while a cubic yard of gravel or concrete can weigh 2,700-4,000 lb or more. Always use the density for the specific material, not a generic estimate, when converting to tons.
Related calculators
Frequently asked questions
How do I convert square feet to cubic yards?
You cannot convert area to volume without a depth. Multiply the square footage by the depth in feet (inches ÷ 12) to get cubic feet, then divide by 27 to get cubic yards. For 300 sq ft at 3 inches deep: 300 × 0.25 = 75 ft³ ÷ 27 = 2.78 cubic yards.
How many square feet does a cubic yard cover?
One cubic yard is 27 cubic feet, so at 3 inches (0.25 ft) deep it covers 27 ÷ 0.25 = 108 square feet. At 2 inches it covers 162 sq ft, and at 1 inch it covers 324 sq ft. Deeper spreads cover less area per yard.
What spread depth should I use?
Mulch is usually spread 2 to 3 inches deep, decorative gravel about 2 inches over a base, topsoil for a lawn 4 to 6 inches, and a concrete slab 4 inches. Use the depth your project actually calls for, since it changes the volume directly.
Why do suppliers sell by the cubic yard?
Bulk landscape and construction materials — mulch, gravel, sand, soil, and ready-mix concrete — are priced and delivered by volume in cubic yards because that is how truck beds and mixers are measured. Converting your area and depth to yards lets you order the right amount.
Sources & references
This tool uses standard formulas and reference values from:
- • American Concrete Institute — ACI 318, Building Code Requirements for Structural Concrete. concrete.org
- • ICC — International Residential Code (IRC), span, footing and framing tables. codes.iccsafe.org
- • APA – The Engineered Wood Association, allowable span and load guidance.
Estimates for planning only. Span, load and code values vary by jurisdiction — verify against your local adopted code and a licensed engineer before building.