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Prices updated January 2026

Concrete Wall Calculator

Cubic yards and bags for a poured foundation or retaining wall — length, height and thickness.

Concrete wall calculator

Shape

Waste factor

Concrete needed (waste in)

5.43 yd³

146.7 ft³ · 4.15

Bags (rounded up)

245

80 lb

326

60 lb

392

50 lb

489

40 lb

Ready-mix (delivered)
$739 – $1,207
Bagged (80 lb)
$1,348 – $2,205
Installed (slab)
$2,200 – $4,800
How much will this cost? →
Concrete 5.43 yd³

Sizing a poured wall

A wall is a flat volume: length × height × thickness. Because walls are usually a full truck or more of concrete, ready-mix is almost always the way to go — the calculator prices it alongside the bag count.

Prices updated January 2026 National US averages · reviewed quarterly

Volumes use standard bag yields and a 10% waste allowance; costs are national US averages that vary by region, mix and finish. See our methodology for exactly how each figure is worked out, or check the reference sources:

Concrete calculators

Frequently asked questions

How much concrete for a wall?
Wall volume is length × height × thickness. A 20 ft wall 8 ft tall and 8" thick needs about 4 cubic yards. Enter your wall above for the exact figure.
How thick is a poured concrete wall?
Residential foundation walls are commonly 8–10" thick; retaining walls vary with height and load. Follow an engineer or local code for structural walls.