What this calculates
A sidewalk is a long, narrow slab. Enter the total run, the walkway width and the thickness to get the exact volume, then itemize cost with your own quotes.
For curved walks, approximate the curve with short straight segments and add them together.
Formula
Volume = length × width × thickness
Total = material + delivery + (labor rate × area) + extras
Cost per ft² = total ÷ (length × width)
Worked example
50 × 3 ft walkway, 4 in thick, example $165/yd³
- 1.50 × 3 × 0.333 = 50 cu ft = 1.85 cu yd
- 2.With 10% waste: 2.04 cu yd → material ≈ $336
- 3.Add delivery and labor from your quotes for the total
Common mistakes
- Forgetting that small pours often trigger short-load fees — sometimes making bags competitive.
- Measuring only the straight sections and missing flares at driveways or steps.
Frequently asked questions
How much concrete does a sidewalk need per foot?
A 3 ft wide walk at 4 in thick uses 1 cu ft per linear foot — about 0.037 cubic yards, or 9 whole 80 lb bags for 5 feet at an example yield of 0.60 ft³ per bag, before waste.
Is it cheaper to bag-mix a sidewalk?
For short walks under about a cubic yard, bags can be practical. Longer runs usually favor ready-mix; compare both with your actual prices above.