Concrete Mix Ratio Calculator
Calculate the right proportions of cement, sand, gravel, and water for different concrete strengths. Covers standard, high-strength, and mortar mixes.
Results
Visualization
How It Works
The classic concrete mix ratio is 1:2:3, one part cement, two parts sand, three parts gravel, yielding about 3,000 psi. Higher-strength mixes use more cement relative to aggregates. The water-to-cement ratio is the most important factor for strength: lower ratios yield stronger concrete but are harder to work. Never exceed 0.50 w/c ratio for exterior concrete. A 94-lb bag of Portland cement equals 1 cubic foot. Always use clean, well-graded aggregates.