How this calculator works
Volume = length × width × depth. Purchase volume = volume × waste factor. Bags = round up(liters ÷ yield per bag).
Worked example
A 3 m × 2 m × 10 cm slab is 0.6 m³. With 10% waste it becomes 0.66 m³, or 660 L. At 12 L per bag, buy 55 bags.
Assumptions to check
- The slab is a rectangular prism with uniform depth.
- Bag yield must come from the product label.
- This is a material-volume estimate, not structural design or building-code advice.