Concrete Calculator

How Much Concrete Do I Need?

The amount of concrete you need depends on the project dimensions. Concrete is measured in cubic yards for ready-mix delivery or bags for smaller projects. A standard 80-lb bag of Quikrete makes 0.6 cubic feet of concrete. One cubic yard equals 27 cubic feet, so you'd need about 45 bags of 80-lb concrete per cubic yard.

Bags vs. Ready-Mix: Which Should You Use?

For projects under 1 cubic yard (roughly a 10x10 slab at 4 inches), bagged concrete is practical. Above 1 yard, ready-mix delivery is almost always better — it's cheaper per yard, saves hours of mixing, and gives you a consistent pour. Most concrete companies have a 1-yard minimum with delivery fees of $50-$150. For anything over 2 yards, ready-mix is a no-brainer.

Concrete Cost in 2026

Ready-mix concrete costs $130-$175 per cubic yard delivered, depending on mix type and your location. An 80-lb bag of Quikrete costs $5-$7 at Home Depot or Lowe's, working out to about $225-$315 per cubic yard — significantly more expensive but convenient for small jobs. For a typical 10x20 patio slab (4" thick), expect to spend $300-$500 on concrete alone, plus $200-$400 for gravel base, forms, and rebar.

Tips for a Successful Concrete Pour

Always order 10% more concrete than your calculation shows — forms are never perfect, and running short mid-pour creates a weak cold joint. Prep your base with 4-6 inches of compacted gravel for drainage. Use rebar or wire mesh for any slab — it adds $50-$100 but prevents cracking. Pour on a mild day (50-80°F) and keep the concrete moist for at least 3 days while it cures. Rushing the cure is the #1 cause of weak, cracking concrete.