Water Cement Ratio Calculator
Calculate the water-cement ratio for concrete and understand its impact on strength, durability, and permeability.
Mix Parameters
Water-Cement Ratio
0.450
180 kg water / 400 kg cement
W/C ratio is within maximum (0.55) for moderate exposure
Est. 28-Day Strength
20.8 MPa
3016 psi
Est. 7-Day Strength
13.5 MPa
1958 psi
Durability
Good
Permeability
Low
Shrinkage
Moderate
For Target 25 MPa
Required W/C Ratio
0.396
Cement Needed
454.9 kg/m³
Water Reduction with Admixtures
Water-Reducing Admixture: Save 18.0 kg (10%)
Superplasticizer: Save 45.0 kg (25%)
Water-Cement Ratio Guidelines
| W/C Ratio | Strength (MPa) | Durability | Application |
|---|---|---|---|
| 0.35-0.40 | 40-50 | Excellent | High performance, marine |
| 0.40-0.45 | 35-40 | Very Good | Bridges, water tanks |
| 0.45-0.50 | 30-35 | Good | Structural members |
| 0.50-0.55 | 25-30 | Fair | General construction |
| 0.55-0.65 | 15-25 | Low | Non-structural |