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Concrete Driveway Calculator

Find how much concrete a driveway needs, with the rebar grid, base gravel and form boards, and the cost.

Change the values and press Calculate to work out your own figures.

Enter the driveway's length, width and thickness.

Size of this dimension.
Size of this dimension.
Size of this dimension.
Center to center, each way.
Compacted gravel under the surface.
For waste, cuts or compaction; for example 10.
For the cost.
Result
Concrete
24.69 cu yd
Cubic feet
666.67 cu ft (18.878 m³)
Premixed bags
2,223 of 40 lb, 1,482 of 60 lb or 1,112 of 80 lb
Weight
about 100,000 lb (at 150 lb/ft³)
Form boards
140 ft (the perimeter)

You need about 24.69 cubic yards of concrete.

Show the working
  1. cubic yards = length × width × thickness ÷ 27 (in feet)

How to use it

Enter the driveway's length, width and thickness.

Lengths can be decimals, fractions or tape entries such as 12' 6 1/2" (in feet or inches). Prices are optional.

Key facts

cubic yards = length × width × thickness ÷ 27 (in feet)

Thickness

4 in suits cars; 5–6 in for heavier vehicles. Mesh is common at 4–5 in, rebar at 5 in and over, in a 12–18 in grid.

Questions

How much concrete for a 20 × 50 ft driveway 8 in thick?

24.69 cubic yards.

Reviewed by RK Calculator Team. Updated 2026-09-26.

Formulas

cubic yards = length × width × thickness ÷ 27 (in feet)

Sources

Limitations

  • Material densities are typical values (the midpoint of the commonly published range); real loads vary with moisture, grading and compaction, so check with your supplier or type in their density.
  • Tank results are the geometric volume; real tanks have wall thickness and fittings.

Formula version 0.1.0Reviewed