Check the path
Your calculation audit
Every total is shown as a short sequence so you can see what was measured, deducted, adjusted and rounded.
- 01Awaiting valid measurementsComplete the fields above to reveal the formula path.
Walls & Masonry
Brick & block calculator
Estimate bricks or blocks for a wall, with opening deductions, waste and optional pack rounding.
Transparent formulaFormula v1.0 · net wall area × selected unit factor × waste allowance
Scope boundary: Materials estimate only — it does not determine specialist designs or project-specific site decisions.
Measure clearly
Simple guidance
Measure the finished length and height of the visible wall face. Measure each door, window and permanent opening at its widest clear opening, then add those areas together.
Worked example
Follow the same logic
A 4 m × 2.4 m wall has a gross face of 9.6 m². Deduct a 1.8 m² opening, then multiply the 7.8 m² net face by the selected brick or block factor before adding waste.
Planning tipWrite down the product factor or pack size you used, so a later change is easy to trace.
Before you buy
Three quick checks
- 01
Measure the finished face, not the ground footprint.
- 02
Add all clear openings together before you calculate.
- 03
Confirm the chosen brick or block coverage and pack size with the merchant.
Quick answers
Useful to know
Should I add a waste allowance?
For straightforward walls, a small visible allowance helps cover cuts, breakage and handling. Use more only when the pattern, shape or site conditions justify it.
Does this include mortar?
No. This tool estimates bricks or blocks only. Mortar quantity depends on the unit, joint, mix and laying method.
Review record
Transparent calculation method
Last reviewed: 2026-10-17. Formula version: v1.0. Classification: wall-material estimate; not specialist design.
Formula source: src/calculator-core.mjs#brickPlan. 60 bricks/m² and 10 blocks/m² are visible selected planning factors, not product specifications.