How to Pour Concrete
Learn how to pour concrete step by step, with the tools, materials, and a free calculator to estimate exactly what you need. To find how much concrete you need, multiply length × width × thickness to get the volume, then convert to cubic yards (divide cubic feet by 27). Add 5–10% for waste. A 10×10 ft slab at 4 inches needs about 1.23 cubic yards, costing roughly $150–$220 in ready-mix.
Get exact numbers
Use the free Concrete Calculator to estimate your project.
Tools
- Tape measure
- Wheelbarrow
- Screed board
- Bull float
- Edging trowel
Materials
- Ready-mix or bagged concrete
- Gravel base
- Rebar or wire mesh
- Form lumber & stakes
Step-by-step
- 1
Measure the area
Record length and width in feet.
- 2
Set the thickness
Convert inches to feet by dividing by 12 (4 in = 0.333 ft).
- 3
Calculate volume
Multiply length × width × thickness for cubic feet.
- 4
Convert to cubic yards
Divide cubic feet by 27.
- 5
Add waste
Multiply by 1.10 for a standard 10% allowance.
Pro tips
- Avoid: forgetting the waste factor — Uneven subgrade and spillage mean you always need a bit more. Add 5–10% so you don't run short mid-pour.
- Avoid: using the wrong thickness — 4 inches suits patios and walkways, but driveways need 5–6 inches. Too thin and the slab cracks under load.
- Avoid: bag-mixing a large pour — Above ~1 cubic yard, mixing bags by hand is slow and risks cold joints. Order ready-mix instead.
- Avoid: ignoring the base and rebar — A compacted gravel base and reinforcement aren't in the concrete volume but are essential — budget for them.