Concrete Mix Calc

Concrete Yard Calculator

Enter your pour below and this concrete yard calculator answers in the unit suppliers use: cubic yards — plus how far one yard goes and what it should cost.

ft
ft
in
$USD

Concrete needed

2.96 yd³

80.0 ft³

Estimated cost

$489

at $165 per yd³

Approx. weight

10,640 lb

≈ 5.3 tons

Bagged mix

134

80-lb bags

178

60-lb bags

267

40-lb bags

Before you order: add about 10% for uneven subgrade and spillage — that's 3.26 yd³ or 147 × 80-lb bags.

Formula

Yards come straight from the volume, and coverage is its inverse:

yards    = [length (ft) × width (ft) × thickness (in) ÷ 12] ÷ 27
coverage = 27 ft² ÷ thickness (ft)   → one yard covers…
  4 in: 81 ft²   5 in: 65 ft²   6 in: 54 ft²

Ordering from the plant? Round up to quarter yards — the ready mix concrete calculator does that rounding for you.

If you're buying bagged mix instead, the how many bags of concrete in a yard guide has the per-bag table and worked project counts.

Example

  1. A walkway 3 ft × 30 ft at 4 inches is 3 × 30 × 0.333 = 30 ft³.
  2. Yards: 30 ÷ 27 = 1.11 yd³ — order 1.25 yd³ with the 10% allowance.
  3. At $165 per yard that's about $206 for the order; in bags it would be 50 × 80-lb.

Frequently Asked Questions

How big is a cubic yard of concrete?

27 cubic feet — think a 3 × 3 × 3 ft cube, about the size of a washing machine. It weighs roughly 3,591 lb (1.8 US tons), which is why a cubic yard is a truck delivery, not a trailer load.

How far does one yard of concrete go?

At 4 inches thick, 81 ft²; at 5 inches, 65 ft²; at 6 inches, 54 ft². Halve the thickness and you double the coverage — thickness is the lever that moves the order size most.

How much does a yard of concrete cost?

Most US markets run $150–$180 per cubic yard delivered, before short-load fees on small orders. The calculator applies whatever price you enter, so plug in your local quote.

Why does the order amount include 10% extra?

Subgrades are never perfectly even, some mix stays in the truck and tools, and forms flex. Ten percent is the industry's standard cushion — running short mid-pour costs far more than the spare concrete.