Concrete Volume Calculator
AvailableWork out how much concrete a flat slab needs in cubic metres and cubic yards.
Use the calculator
The numbers below are examples. Replace them with yours. Everything is worked out in your browser.
About this calculator
Calculate the volume of concrete for a flat slab such as a path, a base or a patio. The result includes a small allowance for spillage and uneven ground, in cubic metres and cubic yards.
How it works
- Volume is length times width times thickness, with the thickness converted from centimetres to metres.
- The order volume is the volume times (1 plus the extra divided by 100).
- One cubic metre is 1.30795 cubic yards.
This is a preliminary estimate for planning and shopping lists. It is not a structural design, a safety check or a building-code approval. Ask a qualified professional before you build.
Common questions
Does this tell me the mix or the number of bags?
No. It gives volume only. Your supplier can tell you the mix and the bags for that volume.
Does it cover footings and reinforcement?
No. It is the volume of a simple slab. Anything structural needs proper design.
Estimates only. Check important numbers before you rely on them.
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