Concrete Mix Design Calculator

Calculate exact quantities of cement, sand, aggregate, and water for any concrete grade — with live 3D mix visualization and PDF report.

Pour Dimensions
Slab or structure length Enter a positive value
Slab or structure width Enter a positive value
Typical slab: 0.15 m Enter a positive value
Enter total volume directly (m³) — overrides dimensions above
Mix Design
M20 = most common residential grade
Adjusts water-cement ratio
Always 1 (reference part)
Parts of sand per cement
Parts of coarse aggregate
Structural range: 0.40–0.55
Water reducer / plasticiser %
Cost per bag
Cost per m³
Cost per m³
⚙  Advanced Settings ▼
Voids factor (default 1.54)
Site loss buffer
Common: 50 kg / 40 kg / 25 kg (metric) · 94 lb / 80 lb / 60 lb (US)
Surface water in sand
Surface water in coarse agg
Live Mix Visualizer
M20
20 MPa · 2,900 PSI
📊  Grade Reference Table ▼
GradeRatio (C:S:A)MPaPSIW/CTypical Application
M5 1:5:10 5 725 0.60 Lean / blinding concrete
M7.5 1:4:8 7.5 1,088 0.60 PCC, mass filling
M10 1:3:6 10 1,450 0.55 Floor bedding, non-structural
M15 1:2:4 15 2,175 0.55 Pathways, lightly loaded slabs
M20 1:1.5:3 20 2,900 0.50 Slabs, driveways, footings (min. RCC)
M25 1:1:2 25 3,625 0.48 Columns, beams, commercial slabs
M30 Design mix304,350 0.45 Bridges, high-load structures
M35 Design mix355,076 0.42 Pre-stressed, multi-storey
M40 Design mix405,800 0.40 High-rise, heavy industrial

IS 456:2000 nominal mixes apply M5–M25. M30+ require designed mix per IS 10262:2019 or ACI 211.1.

📖  How to Use ▼

Step-by-step guide

  1. Enter dimensions — length, width, depth of your pour, or enter total volume directly.
  2. Select concrete grade — M5–M40 (IS 456) or ACI PSI equivalents. Use Custom for your own ratio.
  3. Set workability — Low / Medium / High slump. Automatically adjusts W/C ratio.
  4. Review W/C ratio — auto-set by grade and slump; override if needed. Structural: 0.40–0.55 max.
  5. Admixture % (optional) — water reducer / plasticiser as % of cement weight.
  6. Material costs (optional) — enter local prices to get estimated total cost.
  7. Advanced settings — adjust dry volume factor, wastage %, bag size, moisture corrections.
  8. Results — appear live with every keystroke. 3D visualizer updates in real time.
  9. Download Report — full branded PDF with inputs, results, 3D snapshot, formulas, timestamp.

Key tips

  • M20 is the minimum RCC grade per IS 456:2000.
  • M30+ grades require laboratory-designed mixes — nominal ratios are indicative only.
  • Always add ≥5% wastage for site loss.
  • Lower W/C = higher strength but lower workability.
📐  Formula Used ▼

Volume

Wet Volume (m³) = L × W × D Dry Volume = Wet Volume × DVF (default 1.54)

Material Quantities

Cement (kg) = [C/(C+S+A)] × Dry Volume × 1440 Sand (kg) = [S/(C+S+A)] × Dry Volume × 1600 Agg (kg) = [A/(C+S+A)] × Dry Volume × 1500 Bags = ⌈Cement (kg) ÷ Bag Size⌉

Water & Admixture

Free Water (L) = W/C × Cement (kg) Adjusted = Free Water − Sand moisture − Agg moisture Admixture (L) = (Admix% / 100) × Cement (kg) ÷ 1.2

Wastage & CO₂

With Wastage = Quantity × (1 + Waste% / 100) CO₂ (kg) ≈ Cement (kg) × 0.90 [Portland cement factor]

Unit Conversions

1 m³ = 1.308 cu yd | 1 ft = 0.3048 m | 1 in = 0.0254 m 1 kg = 2.2046 lb | 1 L = 0.2642 gal 50 kg bag = 110.2 lb | 94 lb bag = 42.64 kg

Basis: IS 456:2000, IS 10262:2019 · ACI 211.1 · EN 206. Validate M30+ with laboratory trials.