Concrete Calculator — Slabs, Footings, Columns & Steps
The universal multi-shape construction engine for slabs, Sonotube columns, trench footings, and outdoor concrete steps.
Project Inputs & Specs
Visual Blueprint & Diagram
Total Concrete Required
Yields 58.67 Cu Ft (with 10% buffer)
Order 2.5 Cubic Yards from Ready-Mix Batch Plant
On-site mixing for this volume requires approx: 13 bags Portland Cement, 0.96 cu.yds sand, and 1.91 cu.yds coarse aggregate.
Multi-Shape Geometric Volume Equations
Standard geometric solid equations are calculated in cubic feet, scaled with a 10% jobsite safety factor, and converted to cubic yards:
Slab: L × W × (T ÷ 12) | Column: π × (D ÷ 24)² × H × Qty | Footing: L × (W ÷ 12) × (Depth ÷ 12) | Cu Yds = Cu Ft ÷ 27Step-by-Step Step Rule:
- 1Select your pour shape: Rectangular Slab, Round Pier/Column, Trench Footing, or Steps.
- 2Enter cross-sectional dimensions in feet and inches.
- 3Verify visual geometry schematic to ensure measurements correspond to outer forms.
- 4View both ready-mix cubic yards and dry bag / on-site ratio component yields.
Frequently Asked Questions (FAQ)
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