Calculate concrete volume and bag counts for your slab project. Enter dimensions to get accurate material estimates.
Part of the Concrete & Masonry calculators — see all tools in this category.
Slab length in millimeters
Slab width in millimeters
Typical: 75-150mm depending on use
Typical: 5-10% for simple slabs
Optional: enter cost per cubic meter
Includes 10% waste factor
Without waste factor
Rounded up to full bags
This calculator helps you determine how much concrete you need for a rectangular slab project, whether it's a driveway, patio, shed base, or pathway.
Formula: Volume (m³) = Length × Width × Thickness / 1,000,000,000 (converts mm³ to m³)
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