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🏗️ Concrete & Cement Mix Calculator

Calculate concrete for slabs, footings, and posts with ready-mix or bag estimates

Project Type

Slab Dimensions

How to Use

  1. Select your project type (slab, footing, post holes, or stairs)
  2. Enter the dimensions for your specific project
  3. Click "Calculate Concrete Needed"
  4. See results in cubic yards (for ready-mix) or bags (for DIY)
  5. Add 5-10% for waste and uneven surfaces

Concrete Guide

Ready-Mix vs. Bags

For projects over 1 cubic yard, ready-mix is more cost-effective and easier. For small projects (post holes, small repairs), bags are convenient.

Slab Thickness

4" is standard for slabs, patios, sidewalks. 6" for driveways and heavy loads. Pour on 4" compacted gravel base with vapor barrier for best results.

Mixing Ratios

80 lb bag yields 0.6 cubic feet. 60 lb bag yields 0.45 cubic feet. Mix requires approximately 3 quarts of water per 80 lb bag (follow bag instructions).

Curing

Keep concrete moist for 7 days minimum (spray with water daily). Full strength reached at 28 days. Don't pour if temperature will drop below 40°F within 24 hours.