Concrete calculator
Concrete Calculator — Cubic Yards, Bags & Cost (2026)
How much concrete do I need? Calculate cubic yards, cubic feet, and 60 lb / 80 lb bag counts for slabs, post holes, footings, and cylindrical columns. Includes default 10 % waste and optional cost estimate. Mobile-friendly.
Enter dimensions above to see your result.
Concrete & rebar on Amazon
Each link opens Amazon search with our affiliate tag attached. Pick the bag count that matches the cubic yards the calculator printed above.
- Quikrete 60 lb Concrete Mix ↗
Order one bag per cubic foot, then add 10% for waste.
- Quikrete 80 lb Fast-Setting Mix ↗
For post holes and small footings — sets in 20–40 min.
- 5000 PSI Concrete Mix (high strength) ↗
Use for slabs that carry vehicle loads or hot-tub bases.
- Pre-mixed concrete in a wheelbarrow-ready tub ↗
Skip the mixing drill on small pours.
- 1/2 in × 10 ft rebar #4 ↗
Pairs with the rebar calculator for the slab below this pour.
- Concrete forming lumber (2x4 stakes) ↗
Buy 10% extra — straight forms make a flat slab.
Amazon links may earn Pour Tech a small commission at no extra cost to you — see our Affiliate Disclosure.
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