Concrete Mix Design Calculator (w/c Ratio)
Estimate concrete mix proportions, water-cement ratio, and cement content for a target compressive strength.
Mix Design
Water-Cement (w/c) Ratio From Abrams Law, higher w/c ratios reduce compressive strength. Approximate: w/c = 0.85 − 0.0175 × fc (MPa), clamped between 0.35 and 0.70.
Cement Content Cement content (kg/m³) = Water content (L/m³) / w/c ratio. Minimum cement content is governed by exposure conditions (durability requirements).
Mix Proportions (by weight) Aggregate proportions are estimated from the total volume balance (1 m³ = ~2400 kg/m³ for normal concrete). Fine aggregate ≈ 30–35% of total aggregate by weight; coarse aggregate is the balance.