Concrete Calculator Formula: Cubic Feet to Cubic Yards Explained

Quick Answer

Concrete volume is length times width times thickness. If measurements are in feet, divide cubic feet by 27 to get cubic yards.

Use the [Concrete Calculator](/concrete-calculator) to adjust the dimensions, waste factor, product coverage, and unit price for your exact project.

Formula

``

Cubic yards = length x width x thickness / 27

``

Example Estimate

1. Convert thickness from inches to feet.

2. Multiply length x width x thickness.

3. Divide cubic feet by 27.

4. Add 5% to 15% waste.

Reference Table

| Cubic feet | Cubic yards |

|---:|---:|

| 27 | 1.00 |

| 54 | 2.00 |

| 81 | 3.00 |

Practical Tips

- Do not multiply feet by inches directly.

- Use decimal feet for thickness.

- Round up when ordering ready-mix.

When to Round Up

Round up when the project has cuts, corners, fragile materials, uneven surfaces, delivery minimums, or any chance that matching the same product later will be difficult.

Next Step

Open the [Concrete Calculator](/concrete-calculator), enter your exact numbers, and save the estimate before buying materials.