This cement, sand and aggregate calculator estimates the materials needed for a given volume of concrete and mix ratio. Enter the wet concrete volume and choose the grade.
Cement, Sand & Aggregate Calculator
Formula
Dry volume = wet volume × 1.54. Cement, sand and aggregate are split by the mix ratio; cement bags = cement volume ÷ 0.0347 m³.
How to Use This Calculator
- Enter the wet concrete volume in cubic metres.
- Choose the mix ratio (M15, M20 or M25).
- Click Calculate for cement (bags), sand and aggregate.
Worked Example
For 3 m³ of M20 (1:1.5:3): dry volume = 4.62 m³, giving about 24 cement bags, 0.84 m³ sand and 1.68 m³ aggregate.
Frequently Asked Questions
How much cement, sand and aggregate is needed per cubic metre?
For M20 (1:1.5:3), roughly 8 bags of cement, 0.28 m3 sand and 0.56 m3 aggregate per cubic metre of wet concrete.
What is the dry volume factor for concrete?
About 1.54 — dry materials occupy more volume than the final set concrete.
How many cubic metres is one bag of cement?
One 50 kg bag of cement is about 0.0347 m3 (cement density approx 1440 kg/m3).