Ready-Mix Concrete Calculator

How ready-mix yard rounding works

The calculator measures the raw concrete volume, adds the waste factor, converts cubic feet to cubic yards, then rounds the ready-mix order up to the nearest 0.25 cubic yard.

Quarter-yard rounding is a planning convention, not a guarantee. Your supplier may use a different increment, minimum order size or short-load rule.

Ready-mix order rounding examples

• 10 ft x 10 ft slab, 4 in thick1.23 yd3 before waste; 1.36 yd3 with 10% waste; rounded order 1.5 yd3.
• 10 ft x 12 ft slab, 4 in thick1.48 yd3 before waste; 1.63 yd3 with 10% waste; rounded order 1.75 yd3.
• 12 ft x 12 ft slab, 4 in thick1.78 yd3 before waste; 1.96 yd3 with 10% waste; rounded order 2 yd3.
• 20 ft x 20 ft slab, 4 in thick4.94 yd3 before waste; 5.43 yd3 with 10% waste; rounded order 5.5 yd3.

Before ordering ready-mix

• AccessConfirm the truck can reach the pour or plan wheelbarrow/pump work.
• MinimumsAsk about minimum orders, short-load fees and delivery windows.
• Finish timeHave forms, base, tools and helpers ready before the truck arrives.

Supplier checklist

• Concrete mixAsk what mix strength, aggregate size and slump fit the project and local conditions.
• Rounded quantityShare the calculated yards with waste and ask whether they round by 0.25 yd, 0.5 yd or another increment.
• Minimum orderConfirm minimum yardage, short-load fee, delivery fee and any fuel or environmental charges.
• Truck accessConfirm driveway clearance, overhead wires, weight limits and how close the chute can reach.
• Placement planDecide whether the pour needs chute placement, wheelbarrows, a buggy, conveyor or pump.
• TimingAsk about delivery windows, standby time, unload time limits and cancellation policy.
• Site readinessHave forms, base, reinforcement, tools, helpers and screed boards ready before dispatch.
• WashoutPlan an approved washout area before the truck arrives.

Short-load and delivery questions

Small ready-mix orders may have a short-load fee when the truck is carrying less than the supplier's preferred minimum. That fee can change the bags-vs-ready-mix decision.

Ask for the delivered total, not only the price per cubic yard. Delivery, fuel, environmental charges, standby time, pump service, washout rules and Saturday windows can all affect the final quote.