Concrete Calculator

Estimate how much concrete a slab or a cylinder needs, and the cement, sand and aggregate for a chosen mix ratio. Enter the shape and its dimensions, then pick a mix. This is an approximate estimate for planning and buying materials, not a quote; check local mix designs and requirements. All processing runs locally in your browser. Your data is not uploaded to any server. 100% Local

How to Use the Concrete Calculator

Choose your units and the shape (slab or cylinder). For a slab enter length, width and thickness; for a cylinder enter the diameter and height. Pick a mix ratio and press Calculate concrete to see the concrete volume and the cement, sand and aggregate amounts.

What it accounts for

• Slab volume is length x width x thickness; cylinder volume is pi x radius squared x height.
• A dry-volume factor of 1.54 converts wet concrete volume to dry ingredients, a standard allowance.
• Cement bags are estimated at 1440 kg per cubic metre, rounded up.

Choosing a mix

1:2:4 is a common general-purpose mix. 1:1.5:3 is stronger for structural work. 1:3:6 is a lean mix for non-structural fills. The right mix depends on the job, so confirm it with a local supplier or engineer.

Features

• Slab and cylinder shapes
• Cement bags in 50 kg or 80 lb sizes
• Sand and aggregate by volume
• All processing runs locally in your browser. Your data is not uploaded to any server.
• Results are approximate estimates, not a quote; use a local mix design and check your local building requirements.

For anything structural, always confirm the mix design and reinforcement with a qualified professional and follow your local building code.

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