How to Estimate Concrete Cost: Yards, Waste, Job Cost and Price

Work out the cubic yards from the dimensions. Add the waste allowance you choose and round up to what your supplier delivers. Price that order quantity at your supplier's quoted price per yard. Add labor, equipment, delivery and every other direct cost, then recover overhead. Only then set the selling price from a target margin or a markup. Material cost, total job cost and selling price are three different numbers.

Cubic feet = length (ft) × width (ft) × thickness (ft)

Cubic yards = cubic feet ÷ 27

Thickness is usually measured in inches, so divide it by 12 first: a 4-inch slab is 0.333 ft thick. For an L-shaped or stepped pour, split it into rectangles and add them together. The Concrete Calculator handles multiple sections. The Slab, Driveway and Footing calculators cover those pours by name.

Waste covers spillage, an uneven subgrade, forms that bow, and what stays in the pump or chute. RHACOVA does not assume a waste percentage — choose one from your own past pours and the conditions of this site.

Waste-adjusted yards = cubic yards × (1 + waste %)

Order quantity = waste-adjusted yards, rounded up to your supplier's increment

The calculators default to a 0.25 cu yd increment; change it to match your supplier. Always price the order quantity — that is what you pay for, not the geometry.

Concrete material cost = order quantity (cu yd) × your quoted price per cu yd

Concrete prices vary by supplier, mix, region, season and order size. Use a current quote from your own supplier, not an online average — RHACOVA does not publish or look up concrete prices. Reinforcement is a separate material line; the Rebar Calculator gives bar count and linear feet for a slab grid.

Together these are the direct cost. The full list of cost classes is in what is true job cost.

Price from target margin = total job cost ÷ (1 − target margin)

Margin and markup are not the same figure — see markup vs margin and cost vs price vs profit.

Every price, rate and percentage below is a hypothetical input chosen to show the method — not a current market price, average or recommendation. Replace each with your own.

• Slab 24 ft × 20 ft × 4 in = 160.00 cu ft ÷ 27 = 5.93 cu yd
• 5% waste (example) → 6.22 cu yd, rounded up to the 0.25 increment → 6.25 cu yd ordered

• Concrete — order quantity: $625.00
• Field labor: $600.00
• Equipment: $300.00
• Mobilization and delivery: $150.00

Example inputs: concrete $100.00 per cu yd, 12 labor hours at $50.00 loaded, equipment $300.00, delivery $150.00.

• Direct cost: $1,675.00
• Overhead recovery (10% of direct cost, example): $167.50
• Total job cost: $1,842.50
• Selling price at a 25% target margin (example): $2,456.67
• Expected profit: $614.17 — margin 25.00%, markup on cost 33.33%

The concrete itself is about a third of the price. Pricing from material alone would miss most of the job. Run your own numbers in the Concrete Job Bid calculator.

• Multiplying by thickness in inches instead of feet.
• Dividing cubic feet by 9 (square feet to square yards) instead of 27.
• Leaving out waste, or rounding the order down.
• Pricing the geometric volume instead of the quantity you order.
• Using last season's or an online price instead of a current supplier quote.
• Forgetting pump, short-load, delivery or wait-time charges.
• Pricing labor at the wage instead of the loaded rate.
• Applying a "margin" percentage as a markup, which leaves less profit than intended.