Concrete Footing Calculator

Estimate concrete footing volume, cubic yards, concrete bags, excavation volume, footing cost, soil bearing pressure, required area, and rebar length. Use this concrete footing calculator for deck footings, porch footings, column footings, pier footings, post supports, and small foundation planning.

Calculate Concrete Footing

Concrete volume = footing area × thickness × number of footings. Bearing pressure = load ÷ footing area.
Your result will appear here.

How the concrete footing calculator works

Footing area:
The calculator finds the bottom area based on round, square, rectangular, or continuous strip footing shape.

Concrete volume:
The calculator multiplies footing area by thickness or depth, then multiplies by the number of footings.

Concrete bags and cost:
The calculator adds waste, divides by bag yield, and compares bag cost with ready-mix concrete cost.

Bearing pressure:
The calculator divides load by footing area to estimate soil pressure under each footing.

Why use a concrete footing calculator?

A concrete footing calculator helps estimate how much concrete is needed before ordering bags, ready-mix, rebar, or excavation work.

It can help compare cubic feet, cubic yards, bag count, concrete cost, footing bearing area, soil pressure, excavation volume, and basic footing load checks.

What your result means

Your result shows estimated concrete volume per footing, total concrete volume, cubic yards, concrete bags, estimated bag cost, ready-mix cost, excavation volume, rebar length, footing load, bearing pressure, required bearing area, and simplified soil bearing status. These are planning estimates only.

Concrete footing formulas

Frequently asked questions

How do you calculate concrete for a footing?

Find the footing area, multiply by footing thickness or depth, then multiply by the number of footings. Convert cubic feet to cubic yards by dividing by 27.

How many bags of concrete do I need for footings?

Divide the total concrete volume by the yield per bag, then round up. Add a waste allowance for uneven holes, spillage, and over-excavation.

What is the difference between footing size and concrete volume?

Footing size is based on load and soil bearing. Concrete volume is based on the physical dimensions of the footing. A footing must be both large enough for soil bearing and deep enough for code and construction requirements.

Can this replace footing design?

No. Final footing design should account for frost depth, soil conditions, settlement, concrete strength, reinforcement, uplift, lateral loads, eccentric loads, drainage, local code, and professional review when needed.