Worldwide mortar mix calculator

Mortar Mix Calculator

Calculate sand, cement and lime quantities for common mortar mixes - a recipe bar shows the mix ratio at a glance, and a bag grid shows exactly how many 25kg bags of cement and lime to order.

Metre2 Mortar Mix Calculator showing a proportional recipe bar for the mix ratio, a job section list, and a grid of cement bag icons

Mortar Mix Calculator, in practice

The Calculator tab's recipe bar and bag grid for a real job, and the Mix Guide reference tab.

A recipe bar for the mix ratio

A single proportional bar shows the selected mix design's cement, lime and sand split at a glance - change the mix and the bar updates instantly.

Five standard mix designs

Class (i) through Class (iv), plus a masonry cement mix - each with its typical use, browsable any time in a dedicated Mix Guide tab.

A bag count, not just a volume

Cement and lime totals convert straight to 25kg bag counts, shown as a bag grid - so you know exactly how many to order, not just a raw cubic metre figure.

Six build types

Single-skin and cavity brickwork, two block thicknesses, render (with a coats field) and repointing - each with its own typical mortar volume rate.

Multiple job sections

Add every wall, section or repointing job separately with its own build type and area - totals roll up across the whole job automatically.

Wastage allowance and exports

An editable wastage percentage covers offcuts and spillage. Copy a plain-text summary or export the whole job as a standalone HTML file. Light/dark theme remembers your choice.

How it compares to Buildxact

Buildxact is a well-known cloud estimating and takeoff platform that includes material takeoff as one of many features. It's built for running a whole estimating pipeline, not a quick mix-and-bag-count check - here's how a focused, one-off tool compares.

Feature Mortar Mix Calculator Buildxact
Pricing model One-off purchase after a free trial Subscription, from ~$169/month (Foundation plan)
Works fully offline
Instant standalone mortar mix/bag count ~
Five standard mix designs across six build types, built in
Multiple job sections with a running bag-count total
Full job estimating, quoting & client management
Requires an account/cloud sign-in to use
Wastage allowance you control

Comparison based on Buildxact's publicly listed pricing and features as of August 2026 (buildxact.com, softwareadvice.com, capterra.com) - pricing and features change over time, so check buildxact.com for current details. Buildxact is a trademark of its respective owner; this comparison is for informational purposes and isn't sponsored by or affiliated with Buildxact.

Worked example

Worked example: facing brick, a blockwork garden wall and a chimney repoint

Three different jobs sharing one Class (iii) 1:1:6 mix, added as separate sections so each contributes its own mortar rate.

What goes in

  • Front elevation - facing brick: 42 m², brick, single skin, 10 mm joints
  • Garden wall - blockwork core: 18 m², 100 mm blockwork
  • Chimney repoint: 6 m², repointing
  • Mix: Class (iii) 1:1:6 (cement : lime : sand), 10% wastage allowance

What comes out

  • Wet mortar volume 1.63 m³, dry material volume 2.33 m³
  • Cement: 17 × 25 kg bags · Lime: 17 × 25 kg bags · Sand: 1.75 m³ (≈ 2.8 tonnes)
  • Recipe split shown on screen: cement 13%, lime 13%, sand 75% by volume

The three build types use different mortar rates per square metre (brickwork needs far more than repointing), which is why they are entered as separate rows rather than one lump of area. Pick Class (ii) or masonry cement instead and the lime line disappears or changes - the bag icons redraw as you go. Open the browser edition to try it with your own figures.

Frequently asked questions

Do I need to install anything to use Mortar Mix Calculator?

No - use it straight from your browser, on a phone, tablet or PC, with no sign-up. It works offline once it has loaded, and you can add it to your home screen or desktop like an app. There is also a Windows desktop version in the Microsoft Store if you prefer an installed app.

Does my Mortar Mix Calculator account work with Vector and Forma?

One account covers all of it: Mortar Mix Calculator, Vector, Forma and every other Keystone app share the same sign-in.

Is this an exact match to what I'll actually use?

No - it's an approximate sizing guide based on commonly-used mortar volume rates and standard mix ratios, not a guarantee of exact quantities. Actual requirements vary by brick or block size, joint width, workmanship and wastage on site - always check against your specification before ordering materials.

What mix designs are included?

Five standard mortar mix designs by volume - Class (i) 1:0:4 through Class (iv) 1:2:9, plus a masonry cement 1:4 mix - each with its typical use, browsable in the Mix Guide tab.

Ready to try Mortar Mix Calculator?