Mortar Mix Calculator
Enter total wet mortar volume you want to batch and a cement:sand ratio by volume.
Step 1: Units
Step 2
Enter project measurements
Use decimals if needed (e.g. 3.5).
How to use this calculator
Example ratio 1:3 means one part cement to three parts sand by loose volume before water.
What the math is doing
Cement fraction = ratioC ÷ (ratioC + ratioS). Sand is the remainder of wet volume after shrinkage factor 1.0 (planning only).
Frequently asked questions
Lime?
Add lime as separate ratio line in field notes manually.
Water?
Workability is by mason feel.
Type N vs S?
Does not change volume math here.
Pre-mix bags?
Use bag yield instead.