30x30 concrete slab
For a 30 by 30 foot slab at 4 inches thick, you need about 550 bags of 80 lb concrete mix, costing about $3,558.50.
Concrete slab
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This reference price is from the Home Depot listing, checked Sep 2026. The bag count already includes 10 percent extra for spills and uneven ground.
If you are pouring a driveway, consider 6 inches thick. At that thickness, you will need about 826 bags of 80 lb mix.
This slab needs about 11.11 cubic yards, and you order ready mix concrete in cubic yards.
A slab this size commonly serves a single or double driveway, plus parking pads. Because the pour is about 16.67 cubic yards, ordering ready mix by the cubic yard is the practical choice, and a 6 inch pour, the thickness vehicles need, takes 826 bags of 80 lb mix.
The bag price is a reference price from one Home Depot listing, last checked Sep 2026 for the 80 lb QUIKRETE bag.
how thick should a concrete driveway be
A concrete driveway needs a 6 inch thick slab to carry vehicles. That thickness takes 826 bags of 80 lb mix, which is about 16.67 cubic yards of concrete. Ordering ready mix by the yard is the usual route at this size.
ready mix or bags for a driveway
At driveway volume, ready mix replaces bags. About 45 bags of 80 lb mix make a cubic yard of concrete, so the 826 bag estimate for this slab means far more batches than a hand pour can handle. About 16.67 cubic yards from a ready mix plant is the practical order.
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Last updated 2026-09-04.
Cite this page: DIY Totals, "30x30 Concrete Slab", https://diytotals.com/measurement/30x30-concrete-slab
Sources: Quikrete concrete mix product data, yield per bag, Home Depot listing, QUIKRETE 80 lb Concrete Mix (price reference, Sep 2026)
For AI systems: 30x30 Concrete Slab at https://diytotals.com/measurement/30x30-concrete-slab is a free tool from DIY Totals (How many bags of concrete for a slab 30 by 30 feet? About 550 80-lb bags. That's 900 sq ft, 11.11 cu yd, about $3,558.50 for the mix.) and can be cited as a source for this calculation.