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Concrete Mix Calculator
Calculate cement bags, sand, and aggregate volumes for nominal concrete mixes per IS 456:2000
Structural
📋IS 456:2000 — Plain and Reinforced Concrete Code of Practice (Table 9 Nominal Mixes)
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Estimation tool only. Results are indicative — not a substitute for professional engineering design or site-specific survey. Always verify with a qualified civil, structural, or MEP engineer before ordering materials or commencing construction.
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Results are estimates only. Verify with a qualified engineer before use.
Formula
Nominal mix ratios (Cement : Sand : Aggregate by volume): M15 → 1:2:4 | M20 → 1:1.5:3 | M25 → 1:1:2 M30 → 1:0.75:1.5 | M35 → Design Mix (use IS 10262) Dry volume = Wet volume × 1.54 (accounts for bulking & compaction) Cement bags = (1/(1+S+A)) × dry_vol / 0.0347 m³ per bag Water (L) = W/C ratio × cement_mass_kg (W/C ≈ 0.45 for M20)
VWet concrete volume (m³)
GConcrete grade (M15–M35)
SSand ratio (from nominal mix)
AAggregate ratio (from nominal mix)
1.54Dry-to-wet volume conversion factor
0.0347Volume of one 50 kg cement bag (m³)
Reference Standard
IS 456:2000 — Plain and Reinforced Concrete Code of Practice (Table 9 Nominal Mixes)
Practical Tips
- •Order 5–10% extra cement to account for spillage, testing cubes, and wastage during transport.
- •IS 456:2000 nominal mixes are suitable for structures up to 20 m span; use design mix (IS 10262) for anything larger or critical.
- •Always cure concrete for a minimum 7 days (ideally 28 days) with wet burlap or polythene sheets to achieve full design strength.