WeVividWeVividCalculate cement bags, sand and aggregate for a concrete slab from its size and grade (M15, M20 or M25).
Uses the usual 1.54 dry-volume factor. Add 5–10% for wastage.
M20 concrete (1:1.5:3) needs about 8 bags of 50 kg per cubic metre.
Dry materials shrink when mixed with water, so about 54% more dry volume is needed.
No, plaster uses different mixes and thicknesses.
No. Everything is worked out in your browser and nothing you type is sent to a server.