Why is dry volume 1.54 times wet volume?

Cement, sand and aggregate bulk up with voids when dry. The standard factor for nominal mixes is 1.54, so 1 m³ of wet concrete needs about 1.54 m³ of dry materials.

How many kg is one cement bag?

One standard bag is 50 kg, which occupies about 0.0347 m³. The calculator rounds up to whole bags so you never order short.

Which mix should I choose?

M10/M15 for lean fill and paths, M20 for house slabs and footings, M25 for columns and heavier structural work. Confirm with your structural engineer.

Concrete Calculator - Cement, Sand & Aggregate Quantities

Enter slab dimensions and mix ratio to get cement bags, sand, aggregate and water instantly, with every step shown.

Inputs

Results

Enter your values - results update instantly.

How This Was Calculated

Assumptions

Recent Calculations

Take this result into your project

You are inside AiLoveKit Build - save the result straight into a project BOQ, or keep estimating with the other construction calculators.

Open your projects

Order Concrete Materials Without Guessing

Over-ordering wastes money; under-ordering stalls the pour. AiLoveKit's concrete calculator takes your slab dimensions and nominal mix ratio, applies the standard 1.54 dry-volume factor, and returns cement bags, sand, aggregate and mixing water - with every intermediate step visible so you can audit the math.

How the Calculation Works

Wet volume - length × width × thickness.
Dry volume - wet × 1.54, plus your waste allowance.
Material split - dry volume divided by the mix ratio parts.

Planning a full structure? Try the Brick Calculator and Construction Cost Calculator next, then take everything into your Build projects for a complete bill of quantities.