How to use this calculator
- Enter Footing length in ft.
- Enter Width in in.
- Enter Depth in in.
- Press Calculate. The highlighted row is your order quantity; the note beneath it translates the number into real-world terms.
Formula & constants
Strip footing volume = length × (width ÷ 12) × (depth ÷ 12) ÷ 27 cu yd. A 16 × 8 in footing uses one cubic yard per 30 linear ft. Footings must bear below frost line. Every default in the fields above is editable — when your supplier’s spec sheet lists a different density, coverage rate or price, enter that number instead. The waste and compaction allowances follow common trade practice; see our methodology page for the derivation of each formula and the standards it references.
Where this fits in the project
Concrete work starts below grade: excavation, then a compacted gravel base for drainage, formwork, rebar where the slab spec requires it, then the pour. Order by cubic yard and round up — a short load fee costs more than surplus material.
How this connects to your project
No quantity stands alone — each material in the chain depends on the ones around it. These are the planning steps that pair with the concrete footing calculator:
- Concrete Calculator — Footings are a specific concrete application.
- Concrete Bag Calculator — Small footings use bagged concrete.
- Rebar Calculator — Footings typically contain rebar reinforcement.
- Concrete Column Calculator — Footings support columns and piers.
- Deck Calculator — Deck footings anchor the deck structure.
- Fence Post Depth Calculator — Fence post holes are mini footings.
- Retaining Wall Calculator — Large retaining walls need concrete footings.
- Concrete Slab Calculator — Slab edges may have thickened footings.
Frequently asked questions
How deep must footings be?
Below frost line — 12 in in the South to 48+ in in northern states. Local code governs; heaving destroys shallow footings.
How wide should a footing be?
Twice the wall width as a rule of thumb: 16 in under an 8 in wall on average soils.
Last verified: — prices reflect current national averages. See our methodology.
Estimates are for planning. Material densities, coverage rates and prices vary by region and supplier — confirm final quantities before ordering, and check local code where structural or electrical work is involved.