Sq Ft to Cubic Yards Calculator

Square Feet to Cubic Yards Calculator

Convert area and depth measurements to cubic yards for concrete, gravel, mulch, and soil. Essential for construction, landscaping, and material estimation.

Last updated: March 2026 | By Patchworkr Team

Calculate Volume

ft²

Length × Width = Area (e.g., 25ft × 20ft = 500 ft²)

in

Typical depths: Concrete slab 4", Gravel driveway 4-6", Mulch 2-4"

What is Cubic Yard Conversion?

A cubic yard is a unit of volume measuring 3 feet × 3 feet × 3 feet, or 27 cubic feet total. This is the standard unit for ordering bulk materials like concrete, gravel, mulch, topsoil, and sand in construction and landscaping.

To calculate cubic yards, you need area (square feet) and depth. If you're covering a 500 ft² patio with 4 inches of gravel, you need to convert that area and depth into volume. The formula is: Cubic Yards = (Area in ft² × Depth in inches / 12) / 27.

Understanding cubic yards helps you: order the right amount of materials (avoiding waste or shortages), calculate project costs (materials are priced per cubic yard), plan delivery logistics (know how many truckloads you need), and estimate weight for equipment requirements.

How to Calculate Volume

Step-by-Step Process

  1. 1Measure the area: Length × Width = Square Feet. For irregular shapes, break into rectangles and add them.
  2. 2Determine depth: Measure in inches. Standard depths: concrete slabs 4", gravel driveways 4-6", mulch 2-4".
  3. 3Convert to cubic feet: Area (ft²) × (Depth in inches / 12) = Cubic feet.
  4. 4Convert to cubic yards: Cubic feet / 27 = Cubic yards.
  5. 5Add 5-10% extra: Account for settling, waste, and irregular surfaces.

Conversion Formulas

Cubic Feet = Area (ft²) × Depth (in) / 12
Cubic Yards = Cubic Feet / 27
1 Cubic Yard = 27 Cubic Feet
1 Cubic Yard = 46,656 Cubic Inches

Common Material Depths

Construction
• Concrete slab: 4 inches
• Concrete driveway: 4-6 inches
• Gravel base: 4-6 inches
Landscaping
• Mulch: 2-4 inches
• Topsoil: 4-6 inches
• Gravel pathways: 2-3 inches

Calculation Examples

Example 1: Concrete Patio

Project:
Pouring a 20ft × 25ft concrete patio, 4 inches deep.
Step 1:
Calculate area
20 ft × 25 ft = 500 ft²
Step 2:
Calculate cubic feet
500 ft² × (4 in / 12) = 500 × 0.333
= 166.67 ft³
Step 3:
Convert to cubic yards
166.67 ft³ / 27 = 6.17 yd³
Order:
6.5 cubic yards

(6.17 yd³ + 5% extra for waste)

Example 2: Gravel Driveway

Project:
Covering a 12ft × 30ft driveway with 6 inches of gravel.
Calculation:
Area: 12 × 30 = 360 ft²
Cubic feet: 360 × (6/12) = 180 ft³
Cubic yards: 180 / 27 = 6.67 yd³
Result:
6.67 yd³ ≈ 9 tons

(assuming 1.35 tons/yd³ for gravel)

Frequently Asked Questions

Why measure in cubic yards instead of cubic feet?

Bulk materials (concrete, gravel, mulch) are sold and delivered in cubic yards because it's a more practical unit for large volumes. A cubic yard is easier to visualize and measure for big projects.

How much does a cubic yard weigh?

It varies by material: gravel/aggregate ~1.35 tons, sand ~1.3 tons, topsoil ~1.1 tons, mulch/bark ~0.4 tons, concrete ~4,050 lbs (2 tons). Always verify with your supplier for exact weights.

Should I order extra material?

Yes! Add 5-10% extra to account for settling, compaction, irregular surfaces, and waste. It's cheaper to order slightly too much than to pay for a second delivery for a small shortage.

What if my area isn't a rectangle?

Break irregular shapes into multiple rectangles or triangles, calculate each section separately, then add them together. For circles: Area = π × radius². For very complex shapes, sketch and break into simple sections.

How many wheelbarrows in a cubic yard?

A standard 3 cubic foot wheelbarrow requires 9 trips per cubic yard (27 ft³ / 3 ft³ = 9). A 6 cubic foot contractor wheelbarrow needs 4.5 trips. Plan your labor accordingly!

Can I use this for mulch?

Absolutely! This calculator works for any bulk material. For mulch, typical depths are 2-4 inches. One cubic yard of mulch covers about 108 ft² at 3 inches deep (324 ft³ / 3 in depth).

How do I verify my calculations?

Double-check measurements, use this calculator, then verify with your supplier. Many suppliers have their own calculators—compare results. For expensive materials like concrete, consider having a pro verify before ordering.

What depth should I use for concrete?

Standard concrete slabs: 4 inches. Driveways: 4-6 inches (depending on vehicle weight). Footings and structural elements may need 8-12 inches or more. Check local building codes for requirements.

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