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Quickly estimate how much concrete you need for slabs, footings, posts, and more.

Concrete Bag Calculator

Estimate how many concrete bags you need for slabs, footings, and posts based on volume.

Concrete Bag Volume Calculator

Configuration Details

Select your project type and enter dimensions below to estimate bag requirements.

Related: Concrete Calculator, Gravel Calculator, Material Sheets.

CONCRETE BAG FORMULA

V / 27 = CY × 45 = BAGS

1 cubic yard ≈ 45 bags (80lb). Standard calculation for residential slabs and footings.

Get the Full Concrete Calculator App

Access advanced concrete estimating tools for accurate and efficient planning. Our professional-grade mobile app allows you to perform complex calculations directly on the jobsite.

Take the full calculator with you to the jobsite and unlock powerful estimating tools.

How It Works

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Calculation Example: 1.5 cubic yards = approximately 68 bags (80lb each) including waste factor.

WHY USE THIS CONCRETE CALCULATOR?

Quickly estimate concrete needs

Helps reduce ordering mistakes

Useful for slabs, footings, posts, and walls

Great for contractors and DIY projects

Saves time during project planning

CONCRETE CALCULATOR FAQ

HOW DO I CALCULATE HOW MUCH CONCRETE I NEED?

To calculate concrete volume, measure the length, width, and depth (thickness) of your pour. Multiply these three dimensions to get total cubic feet, then divide by 27 to convert to cubic yards.

HOW MANY CUBIC YARDS OF CONCRETE DO I NEED FOR A SLAB?

A typical 10' x 10' slab at 4 inches thick requires approximately 1.23 cubic yards. Our calculator automates this math for any slab size you enter.

WHAT FEATURES ARE INCLUDED IN THE FULL VERSION?

The full version unlocks slab, footing, post hole, and wall calculations, circular pours, bag counts (80lb, 60lb, 40lb), waste factor adjustments, and professional contractor estimating tools.

Use the free concrete calculator or unlock the full app for advanced estimating tools.

Related: Concrete Calculator, Gravel Calculator.

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