Concrete Calculator for Footings

Estimate concrete for footings and foundations.

Footings are deeper and carry structural load — often 8 inches or more, per your plan and local code. The calculator starts at 8 inches; treat the footing as its area (length × width) at that thickness. Always follow the engineered spec.

Concrete Calculator

Estimate how much you need — and the cost.

Area shape
You need
2.47 cubic yards
112 bags
Also equals
  • cubic feet 66.67
  • cubic meters 1.888
  • tons (US) 5
  • tonnes 4.54

Tip: Footing size and depth are code- and load-specific — confirm dimensions against your plans before ordering.

How it's calculated

1 cubic yard = 27 cu ft, covering about 81 sq ft at 4 in / 54 sq ft at 6 in; an 80 lb pre-mix bag yields about 0.6 cu ft (about 45 bags per cubic yard).

See the full Concrete Calculator for the complete how-to, unit conversions, and data sources.

Concrete Calculator for Footings FAQ

How much concrete for a footing?

Multiply the footing length × width × thickness. A 16 in wide × 8 in deep × 40 ft footing is roughly 1.3 cubic yards.

How deep should footings be?

It depends on load and frost depth in your area — commonly 8 inches or more thick and below the frost line. Follow your plans and local code.

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