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Mortar Calculator

Estimate cement and sand quantities for a target volume of mortar.

Allows for bulking and volume change during mixing.
Enter the required mortar volume and press Calculate.

How the mortar calculation works

The calculator converts your required wet mortar volume to an approximate dry ingredient volume, divides that volume according to the selected cement-to-sand ratio, then estimates cement bags and sand mass using typical bulk-density assumptions.

Choosing a mix ratio

Different masonry, exposure conditions and specifications can require different mortar classes and materials. The ratio selector is for quantity planning, not specification.

Approximate densities and a dry-volume factor are used, so actual quantities vary with moisture, compaction, material grading and mix design. Follow project specifications and product guidance.

Frequently asked questions

Why is dry volume higher than finished mortar volume?

Loose dry ingredients contain voids and change volume when mixed, so more dry ingredient volume is normally required than the final wet mortar volume.

Does this include lime or additives?

No. If the specified mortar includes lime, plasticiser or proprietary additives, follow the specified mix and manufacturer instructions.