Brick Calculator
Brick Calculator works out Units to buy and Blocks to buy from Masonry unit, Wall length and Wall height. The default figures on this page give units to buy of 1,134; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
5 steps
- Wall: 20 ft x 8 ft = 160 ft2 gross = 160 ft2 net.
- Modular brick, nominal 4x2-2/3x8: nominal face 2.6667 in x 8 in = 21.3333 sq in = 0.148148 ft2, i.e. 6.75 units per ft2.
- With 5% waste: 160 x 1.05 = 168 ft2.
- Units = ceil(168 / 0.148148) = 1134.
- Mortar: module 21.3333 sq in less the specified face 2.2917 x 7.625 in, bedded 3.625 in deep, over 1134 units = 9.1811 cu ft.
Its 5 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
3 sources
Keep this result
Save it, change one figure, then compare the two
The calculation stays free. Save this scenario, adjust one assumption, save that too, and put them side by side to see exactly what the change costs you. A free account keeps 5 scenarios and 2 comparisons; Personal makes both unlimited and adds exports and private links. Nothing is saved unless you press Save.
What the Brick Calculator calculates
Counts the concrete blocks, cinder blocks, CMUs or bricks a wall needs from its net area and the unit’s nominal module, then adds mortar joint volume, core-fill grout and material cost.
How to use this Brick Calculator
Enter Masonry unit, Wall length, Wall height and Unit for the wall dimensions. Units to buy updates as you type. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Units to buy, Blocks to buy and Bricks to buy.
The method follows ASTM C90, Standard Specification for Loadbearing Concrete Masonry Units, Brick Industry Association, Technical Note 10: Dimensioning and Estimating Brick Masonry and Researched engineering contracts R390 (block_count) and R400 (brick_count).
What you can compare
Change one input at a time to see how it affects Units to buy, Blocks to buy and Bricks to buy. The inputs you can vary are Masonry unit, Wall length, Wall height, Unit for the wall dimensions, Area of doors, windows and other openings and Net wall area (overrides the dimensions).
Understanding Units to buy, Blocks to buy and Bricks to buy
This is a materials take-off, not a structural design. Wall thickness, reinforcement, grouting and lintels over openings must come from a design by a licensed engineer or from the prescriptive provisions of the code adopted where you build (e.g. TMS 402/602, IRC Chapter 6).
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
See something wrong? Report a problem with this calculator
Frequently asked questions
How do you calculate how much brick you need?
Counts the concrete blocks, cinder blocks, CMUs or bricks a wall needs from its net area and the unit’s nominal module, then adds mortar joint volume, core-fill grout and material cost. Open “How this is worked out” beside the result to see each step for your own figures.
How many bricks for a 10x10 wall?
On the figures this page opens with — wall length 10, wall height 8 and waste and breakage allowance 0% — the units to buy is 1,134. No single number fits everyone: change any figure above and the answer updates as you type, with each step of the arithmetic beside it.
How many bricks are in 1 ft?
It needs Masonry unit, Wall length, Wall height, Unit for the wall dimensions, Area of doors, windows and other openings and Net wall area (overrides the dimensions). Nothing else is required, and the figures stay in your browser.
How much will 1000 bricks cover?
The result gives Units to buy, Blocks to buy, Bricks to buy, Net wall area used, Face area of one unit with joints and Units per area unit of wall, each labelled with its unit so the figure can be read on its own.
What information do I need for the Brick Calculator?
You need Masonry unit, Wall length, Wall height, Unit for the wall dimensions, Area of doors, windows and other openings, Net wall area (overrides the dimensions), Area unit and Face area of one unit including its joints (overrides the unit table). The page opens with default figures that give units to buy of 1,134, so you can see the scale before entering your own.
What does this Brick Calculator show?
It shows Units to buy, Blocks to buy, Bricks to buy, Net wall area used, Face area of one unit with joints, Units per area unit of wall, Units before the waste allowance and Mortar in the joints, with the working and any warnings for your entries.