Square Feet to Cubic Yards Calculator

You're ordering concrete for a patio. Topsoil for a garden bed. Mulch for landscaping. The supplier quotes by the cubic yard. Your measurements are in square feet and inches.

These are two different dimensions — and the square feet to cubic yards calculator connects them cleanly. Area × depth = volume. Then convert to cubic yards. That's the whole process.

Let's break it down completely.

Why Square Feet and Cubic Yards Are Different

Square feet (ft²) measures flat, 2D surface area — length × width.

Cubic yards (cu yd) measures 3D volume — length × width × depth.

To go from 2D to 3D, you need one more piece of information: depth (also called thickness). Without depth, you can't calculate how much material you need — because a 100 sq ft area at 2 inches deep needs completely different material quantities than the same 100 sq ft area at 6 inches deep.

1 cubic yard = 27 cubic feet — that's the conversion constant that ties everything together.

The Square Feet to Cubic Yards Formula

Cubic Yards = (Square Feet × Depth in Feet) ÷ 27

If your depth is in inches, convert first:

Depth in Feet = Depth in Inches ÷ 12

Then apply:

Cubic Yards = (Square Feet × (Inches ÷ 12)) ÷ 27

How the Calculator Works — Inputs Explained

The square feet to cubic yard calculator takes three values:

• Area — enter your surface area in ft² (square feet)

• Height / Depth — enter the thickness of material needed in inches (in) or feet

• Volume — auto-calculated output in cubic inches (cu in) or cubic yards

The calculator handles unit conversion internally — no need to manually convert inches to feet before entering.

How to Calculate Cubic Yards from Square Feet — Step by Step

Step 1 — Find the Area (ft²)

Measure your length and width in feet, multiply them together. Example: 15 ft × 20 ft = 300 sq ft

Step 2 — Find the Depth in Feet

If depth is in inches, divide by 12. Example: 6 inches ÷ 12 = 0.5 feet

Step 3 — Calculate Cubic Feet

Multiply square footage by depth in feet. Example: 300 × 0.5 = 150 cubic feet

Step 4 — Convert to Cubic Yards

Divide cubic feet by 27. Example: 150 ÷ 27 = 5.56 cubic yards

Worked Examples — Real Project Scenarios

Example 1 — Concrete Patio Slab

Patio: 20 ft × 15 ft, 4 inches thick

1. Area = 20 × 15 = 300 sq ft

2. Depth = 4 ÷ 12 = 0.333 ft

3. Cubic feet = 300 × 0.333 = 99.9 cu ft

4. Cubic yards = 99.9 ÷ 27 = 3.7 cubic yards

Order: 4 cubic yards (with waste margin)

Example 2 — Garden Bed Soil

Garden bed: 10 ft × 8 ft, 6 inches deep

1. Area = 10 × 8 = 80 sq ft

2. Depth = 6 ÷ 12 = 0.5 ft

3. Cubic feet = 80 × 0.5 = 40 cu ft

4. Cubic yards = 40 ÷ 27 = 1.48 cubic yards

Order: 1.5 cubic yards of topsoil

Example 3 — Mulch for Landscaping

Landscaping area: 500 sq ft, 3 inches of mulch

1. Area = 500 sq ft

2. Depth = 3 ÷ 12 = 0.25 ft

3. Cubic feet = 500 × 0.25 = 125 cu ft

4. Cubic yards = 125 ÷ 27 = 4.63 cubic yards

Order: 5 cubic yards of mulch

Quick Reference Chart — Square Feet to Cubic Yards by Depth

Bookmark this table — it covers the most common material depths for concrete, soil, gravel, and mulch projects in one glance.

For any area and depth combination outside this chart, CalcyMate converts square feet to cubic yards instantly with any unit input. Explore all construction calculators for concrete, drywall, flooring, and more.

Fun Fact That'll Make You Laugh 😄

A single cubic yard of concrete weighs approximately 4,000 pounds — about the same as a small car.

So when your contractor casually says "we need about 10 cubic yards for this driveway" — they're talking about 20 tons of material being poured into your front yard.

And somehow that still dries smooth enough to park on. Construction is genuinely impressive when you stop to think about it. 😂

FAQs

How do I convert square feet to cubic yards?

Multiply your square footage by the depth in feet, then divide by 27. Formula: Cubic Yards = (sq ft × depth in ft) ÷ 27. If depth is in inches, divide it by 12 first to convert to feet before calculating.

How many cubic yards is 500 square feet at 4 inches deep?

500 sq ft × 0.333 ft ÷ 27 = 6.17 cubic yards. Always round up and add a small waste margin before ordering — especially for concrete pours.

Why do you divide by 27?

Because 1 cubic yard = 27 cubic feet (3 ft × 3 ft × 3 ft = 27). Dividing your cubic feet total by 27 converts the volume into cubic yards — the unit most material suppliers use for bulk orders.

What is 1 cubic yard in square feet?

That depends on depth. At 1 foot deep, 1 cubic yard covers 27 square feet. At 6 inches deep, it covers 54 square feet. At 3 inches deep, it covers 108 square feet. Coverage always increases as depth decreases.

How many cubic yards of mulch do I need for 1,000 sq ft?

At the standard 3-inch mulch depth: 1,000 × 0.25 ÷ 27 = 9.26 cubic yards. Round up to 10 cubic yards to account for settling and uneven coverage across the area.