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Prices updated January 2026

Concrete Calculator — By the Yard

Work out exactly how many cubic yards to order, so you're not left short or paying for concrete you can't use.

Concrete yardage calculator

Waste & region

Order extra for spillage & uneven subgrade. 10% is typical.

Concrete needed (10% waste in)

5.43 yd³

4.94 yd³ of concrete + waste · 400 sq ft

Bags of concrete needed (rounded up)

245

80 lb

326

60 lb

392

50 lb

489

40 lb

Ready-mix (delivered)
$739 – $1,207
Bagged mix (80 lb, DIY)
$1,348 – $2,205
Installed by a pro
$2,200 – $4,800
How much will this cost?

Estimate only — not a quote. Bag counts are rounded up and include a 10% waste allowance.

Concrete 5.43 yd³

Ordering concrete by the cubic yard

Ready-mix plants sell and deliver concrete by the cubic yard (27 cubic feet). Order too little and you risk a cold joint mid-pour; order too much and you pay for waste — so the 10% allowance here is a starting point you can tune under Waste & region.

Rounding your order

Most plants sell in quarter- or half-yard increments. Round your final figure up to the plant's increment, and if you're close to a truckload (about 10 yd³) compare the short-load fee against simply ordering a full load.

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:

More concrete calculators

Frequently asked questions

How many cubic yards of concrete do I need?
Cubic yards = width × length × thickness (in feet) ÷ 27. For a 20×20 slab at 4" that's 400 × 0.333 ÷ 27 ≈ 4.9 cubic yards before waste. Enter your numbers above for the exact figure plus a 10% allowance.
How many cubic yards is a concrete truck?
A standard ready-mix truck holds about 10 cubic yards, though many plants deliver partial loads. Below roughly one truckload, plants add a short-load fee — this calculator includes an estimate of that fee for small orders.
How much is a yard of concrete?
Delivered ready-mix runs about $125–$190 per cubic yard in 2026, before any short-load fee. Small pours cost more per yard because of the minimum-load charge.