Concrete Calculator
Length, width, depth — out comes the volume in cubic feet, the order quantity in cubic yards with your waste factor applied, and bag counts for 60 lb and 80 lb bags, rounded up because a short pour is a bad day.
Planning tool — results are estimates for quoting and ordering, not engineering or building-code advice.
Common questions
How many bags in a cubic yard?
Using standard yields — a 60 lb bag is about 0.45 cu ft and an 80 lb bag about 0.60 cu ft — a cubic yard (27 cu ft) takes roughly 60 of the 60 lb bags or 45 of the 80 lb bags. Past a third of a yard, ready-mix usually beats bagging.
What waste factor should I use?
10% is the common default for slabs on grade. Bump it for uneven subgrade, thickened edges, or hand-mixing spillage.
Does it handle feet and inches?
Yes — dimensions accept tape-measure input like 12' 6" and the depth accepts 3-1/2".
Related: Stairkey for general contracting · Free estimate template
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Concrete & site work
Finishes & materials
This solves one measurement. The Takeoff Builder prices the whole job.
Walk the rooms, enter dimensions, and formula-driven scope turns measurements into quantities, prices, and the estimate itself — from $20/mo, capped, no surprise bills.