Concrete Calculator

Calculate concrete volume and material requirements

Quick answer

Concrete Calculator

Calculate the exact amount of concrete, cement, sand, and gravel needed for your construction project with material cost estimation.

Formula

Volume = Length × Width × Height (+ 10% wastage)

🏗️ Project Details

💰 Cost Estimation (Optional)

📋 Material Requirements

Enter dimensions and click Calculate to see material requirements

🏗️ Construction Tips

  • • 10% wastage is already included
  • • Standard slab thickness: 10-15cm
  • • Footing depth varies by soil type
  • • Always check local building codes
  • • Consider rebar requirements separately

🏗️Formula

Volume = Length × Width × Height (+ 10% wastage)

💡How it works

Calculate the exact amount of concrete, cement, sand, and gravel needed for your construction project with material cost estimation.

ℹ️ What is Concrete Calculator?

A concrete calculator determines how many cubic yards or cubic meters of concrete you need for a project, and how much cement, sand, and aggregate (gravel) to mix. It applies to slabs, footings, columns, walls, steps, and any concrete pour.

📐 Formula

Volume = Length × Width × Depth | Mix ratio: 1:2:3 (Cement:Sand:Aggregate)
Length × WidthSurface area of the pour in feet or meters
DepthThickness of the concrete slab or pour
1:2:3 mix1 part cement, 2 parts sand, 3 parts gravel by volume
W/C ratioWater-to-cement ratio — affects strength and workability

✏️ Worked Example

Slab Length: 20 ft
Slab Width: 10 ft
Thickness: 4 inches (0.333 ft)
  1. 1Volume = 20 × 10 × 0.333 = 66.6 cubic feet
  2. 2Convert to cubic yards: 66.6 / 27 = 2.47 cubic yards
  3. 3Add 10% for waste: 2.47 × 1.10 = 2.72 cubic yards
✅ Result: Order ≈ 2.72 cubic yards of concrete

💡 How to Interpret Results

  • Always add 5–10% extra to account for spillage, settling, and irregular ground.
  • Standard residential slab: 4 inches thick. Driveways: 5–6 inches. Heavy vehicle areas: 6–8 inches.
  • Minimum concrete strength: 2,500 PSI for walkways, 3,000 PSI for driveways, 4,000 PSI+ for structural.
  • One bag (94 lb) of cement + 2 cu ft sand + 3 cu ft gravel ≈ 4.5 cu ft of wet concrete.
  • Cure time: walk on after 24–48 hrs; full strength at 28 days — avoid heavy loads before then.

Frequently Asked Questions

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