Concrete Footing calculator

Calculate concrete for strip and spread footings. Cubic yards, bags, ready-mix loads and weight — with a waste margin built in, nothing leaves your browser.

Dimensions

FIG. 01

Quantity

Waste margin

Volume ÷ 27 = cubic yards. Pros order to the nearest ½ yard and add a waste margin — running short mid-pour risks a cold joint.

You need

—cu yd

Order to nearest ½ yd → — · —

Cubic feet

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Cubic meters

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80 lb bags

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60 lb bags

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Est. weight

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Best buy

see above

How this is calculated

Footing volume is length × width × depth. A continuous (strip) footing uses the full run length; for spread footings, set length and width to the pad size and use the quantity field for multiple pads.

cubic yards = volume in cubic feet ÷ 27 × (1 + waste%)

For the full method and sources, see the methodology page. Comparing buying options? Use the bags-vs-ready-mix calculator.

FAQ

How do I calculate footing concrete?

What is a typical footing size?

Residential strip footings are often 16–24 inches wide and 8–12 inches deep, but the correct size depends on your soil and load — follow your local code and engineer, not a calculator default.