How much concrete for a sidewalk?
Sidewalk concrete is estimated from run length, average width, and thickness. If the sidewalk changes width, has landings, or includes ramps, calculate those sections separately.
Common sidewalk example
A 40 ft long by 4 ft wide sidewalk at 4 inches thick is about 1.98 cubic yards before waste. Adding 10% waste brings the planning number to about 2.17 cubic yards.
Sidewalk layout notes
Curves, approaches, curb transitions, accessibility requirements, drainage, and control joints can affect the real project even when the volume math is simple.
Common concrete slab sizes
Cubic yards below are before waste. Add your project waste percentage before ordering.
| Slab size | 4 in thick | 5 in thick | 6 in thick |
|---|---|---|---|
| 10 ft x 10 ft | 1.23 cu yd | 1.54 cu yd | 1.85 cu yd |
| 10 ft x 12 ft | 1.48 cu yd | 1.85 cu yd | 2.22 cu yd |
| 12 ft x 12 ft | 1.78 cu yd | 2.22 cu yd | 2.67 cu yd |
| 20 ft x 20 ft | 4.94 cu yd | 6.17 cu yd | 7.41 cu yd |
| 24 ft x 24 ft | 7.11 cu yd | 8.89 cu yd | 10.67 cu yd |
| 30 ft x 40 ft | 14.81 cu yd | 18.52 cu yd | 22.22 cu yd |
Before you calculate
- Measure the sidewalk run length and average width in feet.
- Use the planned sidewalk thickness in inches and calculate separate sections if width changes.
- Add separate estimates for landings, ramps, approaches, or curves.
Common mistakes
- Measuring only the centerline length without accounting for width changes.
- Forgetting landings, transitions, curb cuts, or widened sections.
- Ignoring slope, drainage, and local accessibility requirements.
Formula
cubic yards = (length * width * (thickness / 12) / 27) * (1 + wastePercent / 100)
Assumptions
- Concrete quantity is a planning estimate, not structural design.
- Thickness, subgrade, forms, reinforcement, slopes, and local requirements should be checked separately.
- Round ready-mix and bagged materials up before ordering.
Example
Estimated concrete needed (cubic yards): 0.54 cubic yards
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 Garage Sidewalk Landing Concrete Calculator result to plan materials.
Before you buy materials
- Round ready-mix orders to supplier increments and confirm short-load fees.
- Use the estimate as material planning, not as sidewalk design or code approval.
FAQ
What is the example garage sidewalk landing concrete cubic-yard result?
Use length, width, thickness or depth, and waste, then calculate the planning result. In the default example, the result is 0.54 cubic yards.
How do I calculate sidewalk concrete?
Multiply sidewalk length by width, multiply by thickness in feet, divide by 27, then add waste if needed.
How much concrete for a 40 ft sidewalk?
At 4 ft wide and 4 inches thick, a 40 ft sidewalk needs about 1.98 cubic yards before waste.
Should I calculate sidewalk sections separately?
Yes, calculate separate sections when width, thickness, slope, or shape changes.
Does this calculate sidewalk code requirements?
No. It estimates concrete quantity only. Check local requirements for thickness, slope, reinforcement, and accessibility.
Related calculators
This calculator is for planning estimates only. Verify final quantities with product labels, project conditions, and a qualified professional when accuracy matters.