Mortar Mix and Repointing Calculator
Estimate mortar bags and editable cost either from masonry-unit count or from repointing-joint volume.
How to use the mortar calculator
- Measure the actual project. Break irregular work into separate sections and record finished dimensions consistently.
- Enter the core measurements. The quick view focuses on project geometry; add or subtract sections where the calculator supports multiple areas.
- Review purchasing assumptions. Open Advanced inputs to replace example prices, waste, coverage, density, pack size, minimum order, or delivery assumptions with current project information.
- Calculate and verify. Review the formula, limitations, whole-unit rounding, product instructions, and supplier requirements before purchasing.
Key inputs covered: Calculation mode, Brick or block count, Units covered per bag, Total joint length, Joint width, Raking/fill depth, Mixed mortar yield, Waste allowance, Bag example price.
Result coverage: The mortar calculator reports 6 separate quantities so the primary estimate and its supporting purchase or planning values can be checked together.
How the estimate works
New-work mode divides masonry units plus waste by editable bag coverage; repointing mode divides joint length × width × depth plus waste by mixed bag yield.
QUIKRETE publishes approximate per-bag coverage for standard bricks and blocks; enter the selected product's value.
Assumptions, rounding, and limitations
Dimensions are treated as finished measurements. Only deductions and allowances entered above are included. Decimal measurements display to two places; purchase quantities round up when a whole container or piece is required.
- Coverage changes with unit size, joint profile, workmanship, loss, and product.
- Match mortar type and compatibility to the masonry and project specification.
- Repointing historic masonry requires compatible materials and qualified assessment.
Sources and review
These references support unit conversions and selected planning assumptions. Product instructions and local requirements control the actual project.
Last reviewed: 2026-10-09
Editorial process
BuildPlanCalc publishes the formula, editable assumptions, limitations, and supporting references so the estimate can be checked rather than treated as a black box. See the calculation and review methodology, or report a correction.
Frequently asked questions
Are the results exact?
No. Results are planning estimates based on the dimensions and assumptions entered. Confirm product coverage, site conditions, and ordering rules with the supplier.