How Many Bags of Concrete Do You Need? (Calculator + Charts)
How many bags of concrete you need = total volume ÷ bag yield. One 80-lb bag yields 0.6 ft³ (~45 per cubic yard). Project cheat tables for slabs, footings, posts, and sonotubes.
Concrete Bags
Guides & tutorials that support the Concrete Bags Calculator.
How to Estimate Bags of Concrete for Any Project
Full method — measure formwork dimensions, apply the 1.54 dry-volume factor, choose between mix-ratio batching and pre-mix yield, then translate to bag counts for any slab, footing, or column.
Concrete Bags Per Cubic Yard — Full Reference Tables for All Bag Sizes
Complete bags-per-yard tables for 40/50/60/80 lb bags — fractional yards, full 0.25–5.0 yd³ lookup, project quick-reference, and the switch-to-ready-mix threshold.
Dry Pour Concrete Method: Bag Count by Area, Depth & Hole Size
Dry-pour concrete places dry bagged mix directly into a hole — no pre-mixing required. This guide covers the bag-count formula by square feet and depth, worked examples for fence posts and pads, a quick-reference table for 40/60/80 lb bags, and when the method is safe to use.
Understanding Concrete Bag Coverage and Yield
Typical yields per bag size with coverage examples at common slab thicknesses.
Concrete Bag Size Differences: US vs Australia vs UK
A practical comparison of common retail bag sizes across regions and how they affect counts.
Concrete Bag Calculation Hub: Every Method, Formula & Project Chart
The index to every concrete-bag guide on the site — methods, conversions, and project-specific bag charts, each linked to its in-depth tutorial. Start here, then dive into the specifics.
Building a Retaining Wall? How Many Concrete Bags You’ll Need
Sizing concrete for small retaining walls using bag counts with safety buffers.
How Many Bags of Concrete for Fence Posts?
Diameter, depth, and spacing guidelines to figure out post-hole bag counts.
Featured Tool
Need instant results? Use the Concrete Bag Calculator.