How much concrete do I need?

Enter your slab or footing length, width and thickness, or a round column's diameter and depth. You get the volume in cubic yards and cubic metres, a waste allowance, and the rounded-up ready-mix order.

Does it order concrete in cubic metres for Canada?

Yes. Measure in imperial and still see the order in cubic metres side by side. Canadian ready-mix is sold by the cubic metre.

Does it calculate rebar too?

Yes. Enter slab size, bar size, spacing and cover from your drawings and it counts the bars to buy, the grid and any lap splices. It counts to your spec; it does not design the steel.

SCOPE LOGIC

Free contractor tools

Free Concrete & Rebar Calculator

Get your ready-mix order and your full rebar grid in seconds — each with the exact formula and the standard behind every number. No sign-up.

Runs on the same estimating engine ScopeLogic uses to price real jobs.

Your pour

Length (ft)

Width (ft)

Thickness (in)

How many of these? (same size)

Pouring several the same size — like 6 deck footings? Enter the count and we add them up. Just one slab? Leave it at 1.

Waste allowance Our default 10%

Concrete waste runs about 5–10%. We default high and round up — a short pour turns into a cold joint, not a rounding error.

Concrete you need

5.43yd³

=4.15 m³

You need to order 5.50 yd³ of ready-mix

How we got this

Source: 1 yd³ = 27 ft³ · 80 lb bag = 0.60 ft³ · ready-mix by yd³ (US) / m³ (Canada) · waste rounded up per concrete good-practice.

Free calculators — no sign-up. Powered by ScopeLogic.

But a pour is never just concrete

The mud and the steel are the easy part. Here's the rest of a real bid.

You've got concrete and rebar dialed in. But quote a client off just those two and you're leaving out the parts that actually make or lose you money on the job.

Concrete — done
Rebar grid — done
Gravel base & vapour barrier
Forms & stripping
Place, finish & cure labour
Your markup & the client price

Your numbers, grown up

The same concrete and steel, turned into a bid you'd actually send.

In ScopeLogic those quantities flow straight into a full estimate — every companion material, labour and your markup — and come out as a clean proposal your client can approve and pay online.

Estimate — Rear garage slabExample

Line item	Qty	Unit	Your price
Ready-mix concrete, 32 MPafrom calculator	5.5	yd³	$1,788
Rebar 15M grid, 12″ o.c.from calculator	40	bars	$680
Granular base, 6″ compacted	7.4	yd³	$318
Poly vapour barrier, 6 mil	440	ft²	$92
Forms — 2×10, set & strip	82	lin ft	$430
Place, finish & cure — labour	20	hr	$1,400
Client proposal total			$4,708

Your cost and markup stay private — the client only ever sees the price.

Want the whole takeoff & estimating platform — not just the calculator? Try ScopeLogic free for 7 days →

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Free for 7 days — no charge today. Cancel anytime. Solo $39 · Crew $69 · Pro $99 /mo after trial.