Concrete Footing Calculator
Plan continuous footings with clear length, width, and depth measurements. Switch between US customary and metric units, adjust the assumptions, and keep every step visible.
A visible formula, not a black box.
Inputs are converted to a common base unit before calculation. Purchase quantities are rounded only at the final buying boundary.
Example: 40 ft of continuous footing
A 16 × 8 in section with 10% allowance produces about 1.45 yd³. Use dimensions from the approved plan.
Use this to understand the workflow—not as a recommendation for your project.What supports this calculation.
The named mix lists footings as an intended use; footing dimensions still come from approved project documents.
Mathematical derivationNIST SI conversion factors ↗Exact length, area, and volume unit conversions; the project formula is derived from standard geometry.
Check the job, not just the number.
- 01Leaving the example concrete footing inputs unchanged instead of entering measured project values.
- 02Treating an editable coverage, size, density, or allowance as universal instead of checking the selected product label, project documents, and local requirements.
- 03Ordering from the rounded result without reviewing exclusions: Add the centerline length of every continuous footing section. Verify footing dimensions against the approved plan and local requirements.
Concrete footing FAQ
What does the Concrete Footing Calculator estimate?
Plan continuous footings with clear length, width, and depth measurements. The primary output is volume, with the intermediate assumptions kept visible.
How is the concrete footing result calculated?
The visible formula is: volume = total length × width × depth × (1 + waste allowance). Inputs are converted to a common base unit before the final purchase boundary is rounded.
Are the default values recommendations?
No. Dimensions are worked examples and product-dependent presets are planning defaults. Replace them with the selected product label, project documents, and local requirements.
Is the result ready to order from?
Use it as a checked planning estimate, then confirm packaging, minimum orders, installation instructions, site conditions, and any code or professional-design requirements.