Coverage depends on thickness
A cubic yard is a volume, so it does not convert to one fixed square-foot number. Coverage depends on slab thickness. One cubic yard covers about 81 sq ft at 4 inches thick, 65 sq ft at 5 inches thick, and 54 sq ft at 6 inches thick.
How to convert cubic yards to square feet
First convert thickness to feet. Then divide 27 cubic feet by that thickness in feet. For example, at 4 inches thick, thickness is 0.333 ft, so 27 / 0.333 is about 81 sq ft per cubic yard.
Coverage examples
Two cubic yards cover about 162 sq ft at 4 inches thick, about 130 sq ft at 5 inches thick, or about 108 sq ft at 6 inches thick. Add waste or ordering margin separately when planning a pour.
Use square-foot coverage as a check
Coverage tables are useful for quick checks, but final ordering should still use the project dimensions, slab thickness, and waste. Uneven base, forms, and over-excavation can change real usage.
Concrete coverage by thickness
Coverage assumes 1 cubic yard of concrete, which is 27 cubic feet. Waste is not included.
| Thickness | Sq ft covered by 1 cu yd | Sq ft covered by 2 cu yd |
|---|---|---|
| 3 in | 108 sq ft | 216 sq ft |
| 4 in | 81 sq ft | 162 sq ft |
| 5 in | 65 sq ft | 130 sq ft |
| 6 in | 54 sq ft | 108 sq ft |
| 8 in | 41 sq ft | 81 sq ft |
Before you calculate
- Measure the actual formed length and width in feet.
- Enter slab thickness in inches, then handle thickened edges or footings as separate estimates.
- Break irregular slabs into rectangles so the volume calculation stays transparent.
Common mistakes
- Using square feet without converting thickness into volume.
- Missing thickened edges, turndowns, steps, or separate pads.
- Ordering exactly the calculated amount with no allowance for site variation.
Formula
cubic yards = (length * width * (thickness / 12) / 27) * (1 + wastePercent / 100)
Assumptions
- The calculator uses length, width, and thickness.
- Thickness is entered in inches.
- Coverage depends on slab thickness.
Example
Estimated concrete needed (cubic yards): 1 cubic yard
How to use this calculator
- Enter length in ft.
- Enter width in ft.
- Enter thickness in in.
- Enter waste in %.
- Review the live estimate and compare it with the example result.
- Check the formula, assumptions, product labels, and site conditions before using the Cubic Yard of Concrete to Square Feet Calculator result to plan materials.
Before you buy materials
- Compare cubic yards, cubic feet, and bag counts before deciding between ready-mix and bags.
- Confirm final slab details with plans, product labels, or a qualified professional when accuracy matters.
FAQ
What is the example cubic yard of concrete to square feet cubic-yard result?
Use length, width, thickness or depth, and waste, then calculate the planning result. In the default example, the result is 1 cubic yard.
How many square feet are in a cubic yard of concrete?
There is no single answer without thickness. One cubic yard covers about 81 sq ft at 4 inches, 65 sq ft at 5 inches, or 54 sq ft at 6 inches.
How many square feet does 2 yards of concrete cover at 4 inches?
At 4 inches thick, 2 cubic yards covers about 162 square feet before waste.
Why does thickness change concrete coverage?
Thicker concrete uses more volume per square foot. The same cubic yard spreads over less area when the slab is thicker.
Can I use this to order ready-mix?
Use coverage as a quick check, then calculate the final order from length, width, thickness, and waste before contacting a supplier.
Related calculators
This calculator is for planning estimates only. Verify final quantities with product labels, project conditions, and a qualified professional when accuracy matters.