Square Feet to Cubic Yards Calculator: Free Online Conversion Tool
Use our free square feet to cubic yards calculator to turn an area measurement into a volume by adding depth. Enter the total square footage of your project along with the desired depth to instantly get cubic feet, cubic yards, and cubic meters. Ideal for concrete slabs, asphalt paving, gravel beds, and mulch coverage.
How to use this calculator.
- Enter the total area. Input the square footage of your project area. If you don't know this yet, calculate it first by multiplying length by width.
- Enter the depth. Provide the material depth in inches. This is the thickness of the layer you plan to install.
- Click calculate. The results show volume in cubic feet, cubic yards, and cubic meters instantly.
- Add a waste factor. Multiply the cubic yards result by 1.05 to 1.10 to account for compaction and spillage.
- Order in whole yards. Most suppliers sell concrete and aggregate by the full or half cubic yard, so round your final figure up to a practical order quantity.
How do you calculate cubic yards from square footage?
To convert square feet to cubic yards, first convert the area to cubic feet using the depth, then convert cubic feet to cubic yards (and cubic meters, if you need the metric equivalent).
Cubic Feet = Area (sq ft) × (Depth (in) ÷ 12)
Cubic Yards = Cubic Feet ÷ 27
Cubic Meters = Cubic Feet ÷ 35.3147
Where:
- Area: The total surface area in square feet (length × width).
- Depth: The thickness of the material layer, in inches, divided by 12 to convert to feet.
- 27: The number of cubic feet in one cubic yard (3 ft × 3 ft × 3 ft).
- 35.3147: The number of cubic feet in one cubic meter, used to get the metric equivalent.
Example calculation.
Scenario: You have a patio area of 400 square feet and want a 4-inch thick concrete slab.
- Convert depth to feet: 4 in ÷ 12 = 0.333 ft
- Calculate cubic feet: 400 sq ft × 0.333 ft = 133.33 cu ft
- Convert to cubic yards: 133.33 cu ft ÷ 27 = 4.94 cu yd
- Convert to cubic meters: 133.33 cu ft ÷ 35.3147 = 3.78 m³
- Add 10% waste: 4.94 cu yd × 1.10 = 5.43 cu yd
Result: The slab needs approximately4.94 cubic yards (133.33 cu ft, 3.78 m³) of concrete, or about 5.5 cubic yards once waste is factored in.
Tips from the field.
- Memorize the 324 shortcut. Area (sq ft) × Depth (in) ÷ 324 gives cubic yards directly — the fastest jobsite estimation method, and mathematically the same as the two-step formula above.
- Common depth-to-cubic-yard references. At 4 inches deep, one cubic yard covers 81 sq ft. At 2 inches deep, it covers 162 sq ft. At 6 inches deep, it covers 54 sq ft.
- Use it for partial areas on larger projects. When only a portion of a project needs a different depth (thickened slab edges, for example), calculate that portion's square footage separately and run it through this calculator on its own.
- Don't skip the metric check. If you're working from an international spec or importing material priced in cubic meters, confirm the m³ figure before you place the order — 1 cu yd is only about 0.76 m³.
Disclaimer: This calculator provides estimates for planning purposes only. Actual material requirements vary based on site conditions, compaction, and waste. PavementCalculator.com assumes no liability for material overages or shortages.
Cost, price, and density figures on this page reflect approximate U.S. averages as of August 2026 and vary by region, supplier, and material availability.
Frequently asked questions.
How do you convert square feet to cubic yards?
Multiply the area in square feet by the depth in feet (inches / 12) to get cubic feet, then divide by 27 to get cubic yards. For example, 1,000 sq ft at 6 inches deep = 1,000 × 0.5 = 500 cubic feet / 27 = 18.52 cubic yards. Our calculator above does this instantly.
How many cubic yards are in 1,000 square feet?
It depends on the depth. At 1 inch deep: 3.09 cubic yards. At 3 inches deep: 9.26 cubic yards. At 6 inches deep: 18.52 cubic yards. At 12 inches deep: 37.04 cubic yards. Enter your exact area and depth above for a precise result.
How much mulch do I need per square foot?
One cubic yard of mulch covers approximately 324 sq ft at 1 inch depth, 162 sq ft at 2 inches, 108 sq ft at 3 inches, or 81 sq ft at 4 inches. Use our calculator above with your exact area and desired mulch depth.
What is the formula for square feet to cubic yards?
The formula is: Cubic Yards = (Area in sq ft × Depth in feet) / 27. Remember to convert depth from inches to feet by dividing by 12. For example: (1,000 sq ft × (6/12) ft) / 27 = 18.52 cubic yards.
How do I convert square feet to cubic yards?
Multiply square feet by depth in feet (inches ÷ 12), then divide by 27. For 500 sq ft at 4 inches: 500 × (4÷12) ÷ 27 = 500 × 0.333 ÷ 27 = 6.17 cu yd. This is the most common conversion for ordering mulch, gravel, soil, and concrete.
Can I use this for irregular shapes?
Yes. Calculate the total square footage of the irregular area first (by breaking it into rectangles or using the average width method), then enter that total area into this calculator with your desired depth.
How does depth affect the cubic yard calculation?
The cubic yard requirement scales linearly with depth. Doubling the depth doubles the cubic yards needed. For example, 200 sq ft at 2 inches needs 1.23 cu yd, while at 4 inches it needs 2.47 cu yd.