# Square Feet to Cubic Yards Calculator

URL: https://speedycalculator.com/calculators/construction/square-feet-to-cubic-yards/
Last updated: 2026-10-25

> The square feet to cubic yards calculator converts an area in square feet and a depth in inches into cubic yards, cubic feet and cubic metres, so you can order mulch, soil, gravel or concrete for a known area.

## Inputs

- Area (ft², m², yd², acre)
- Depth (in, cm, mm, ft, m)
- Extra allowance (%)
- Price per cubic yard (optional) (/yd³, /m³, /ft³)

## Results

- Volume
- Volume in cubic feet
- Cost

## Formula

```
Cubic yards = area (ft²) × depth (ft) ÷ 27 = area (ft²) × depth (in) ÷ 324
```

## Explanation

Square feet measure area, cubic yards measure volume, so you need a depth to convert between them. That is exactly the situation when you know the size of a bed, patio or slab and want to order bulk material. A quick rule: one cubic yard covers 324 ft² at an inch deep.

### How to use the Square Feet to Cubic Yards Calculator

- **Area**
- **Depth**
- **Extra allowance**
- **Price per cubic yard (optional)**
- Every result field is editable: type into **Volume** and **Depth** plus every other field update to match.

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Enter the area and the depth of the layer, plus an optional extra allowance. The calculator multiplies area by depth and divides by 27 ft³ per yd³. You can also type the cubic yards you have to find the depth they will cover.

### Quick reference: cubic yards per 100 ft²

Depthyd³ per 100 ft²1 in0.3092 in0.6173 in0.9264 in1.2356 in1.8528 in2.46912 in3.704

### Tips for an accurate estimate

- Measure every dimension twice and write the unit next to each number – most estimating errors are unit mix-ups (inches entered as feet).
- Pick the unit in each field's menu instead of converting by hand; the calculator converts everything to the same base before it multiplies.
- Round up only at the very end. Rounding each dimension first can add several percent to the final quantity.
- Suppliers sell in whole units – bags, boxes, sheets or quarter yards – so always round the final order up, not down.

### Common mistakes to avoid

- Mixing square and cubic units: square feet measure area, cubic yards measure volume, and you need a depth to go from one to the other.
- Using nominal lumber sizes where actual sizes matter (a 2×4 is really 1½ × 3½ in).
- Forgetting that 1 yd³ = 27 ft³, not 9 ft³ (9 is for square yards).

### Inputs explained

FieldWhat to enterAreaUnits: ft², m², yd², acreDepthUnits: in, cm, mm, ft, mExtra allowanceIn %Price per cubic yard (optional)Units: /yd³, /m³, /ft³

### What each result means

- **Volume** = [Area]×[Depth]×(1 + [Extra allowance]÷100)
- **Volume in cubic feet** = [Volume]
- **Cost** = [Volume]×[Price per cubic yard (optional)]

## Worked example

Inputs — Area: 400 ft²; Depth: 3 in; Extra allowance: 0 %; Price per cubic yard (optional): $0 /yd³.

Results — **Volume = 3.704 yd³**; Volume in cubic feet = 100 ft³; Cost = $0.00.

## FAQ

**How many square feet does a cubic yard cover?**
324 ft² ÷ depth in inches – so 108 ft² at 3 in or 81 ft² at 4 in.

**How do I convert square feet to cubic yards without depth?**
You can't; area and volume are different quantities. Pick the depth you plan to spread.

**How many cubic yards for 1,000 ft² at 4 inches?**
1,000 × 4 ÷ 324 = 12.35 yd³.

**What formula does the Square Feet to Cubic Yards Calculator use?**
Cubic yards = area (ft²) × depth (ft) ÷ 27 = area (ft²) × depth (in) ÷ 324.