Overview
Mortar Calculator is a free online estimating tool that figures out how much mortar a masonry project requires from wall dimensions, unit type and mortar mix. Enter length, height, thickness and joint size, then pick a brick or block preset and a mortar type (N, S, M or O) to get the mortar volume plus material breakdowns for pre-mixed bags or a DIY cement, lime and sand mix. A live build diagram, imperial/metric toggle, adjustable waste factor and coverage guidance make it ideal for masons, builders and DIYers ordering the right amount in one trip.
Our take
A free mortar calculator for brick, block and stone work, requiring no account. Materials estimating is straightforward arithmetic that is easy to get wrong under time pressure, which is what tools like this are for. The estimate is a starting point — waste, joint width and mix ratio all shift the real requirement.
Worth it if
Estimating mortar quantities for masonry projects before ordering materials.
Look elsewhere if
Structural specification, which is an engineering decision rather than a quantity calculation.
✨ Features
Mix-Aware Estimates
Choose mortar type N, S, M or O and get accurate volume for your job.
Bag & DIY Breakdown
See both pre-mixed bag counts and a cement, lime and sand recipe.
Live Build Diagram
Visualise the wall as you enter dimensions and unit presets.
Waste Factor & Units
Add a surplus percentage and switch between imperial and metric.
⚖️ Pros & Cons
Pros
Cons
💰 Pricing
Free
$0
- All mortar type calculations
- Bag and DIY mix breakdowns
- Live build diagram
- Waste factor, free
Categories
❓ Frequently Asked Questions
How much waste should I allow?
Typically five to ten percent for straightforward work and more for complex layouts, irregular stone or difficult access. Mortar also has a working life once mixed, so mixing in batches sized to what you can lay avoids the waste that comes from material going off in the tub.
Does the mix ratio change the quantity needed?
It changes the proportions of cement, lime and sand rather than the total volume of mortar substantially. What actually drives quantity is joint width and unit size — a ten millimetre joint versus a fifteen millimetre one is a large difference across a whole wall, much larger than mix variation.