Calculators · Dirt & site work

Concrete slab calculator

Yardage for a flat pour, plus what it is in bags if you're mixing on site.

How it is worked out

length × width × (thickness ÷ 12) = cubic feet ÷ 27 = cubic yards

What it assumes

Waste covers spillage, an uneven subgrade and the last wheelbarrow you always need. 10% is the common allowance; short-load fees make under-ordering the expensive mistake.
Bag yields are the manufacturer's own numbers: an 80 lb bag makes 0.60 ft³, a 60 lb bag 0.45 ft³.

This is the same calculator that is in your Hub

Nothing on this page is a demo of the real thing — it runs the identical code. What a TradeForge account adds is everywhere the number then goes: saved against the job it belongs to, dropped straight onto a quote, and priced at a rate built from your own overhead instead of a guess.

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