📚 What's in This Guide
This brick calculator tells you how many bricks to order for a wall, and it can also estimate the mortar and the material cost. Enter the wall length and height, add any doors and windows, choose a brick size and mortar joint, and you get the net count plus the quantity to buy once waste is included. It suits homeowners planning a garden or boundary wall, contractors checking a quote, and anyone comparing brick sizes before they buy.
An accurate count matters because bricks are sold in full packs, a short order can stall the job, and a second batch may not match the first. Use the calculator above, then read on to see exactly how the numbers are built.
Bricks = net wall area ÷ the area of one brick plus its mortar joint. With modular brick and 3/8 inch joints that is about 6.86 bricks per square foot, so 100 square feet of wall needs about 686 bricks before waste. Add 5 to 10 percent for breakage and cuts, and double the count for a wall two bricks thick.
1. How the Brick Calculator Works
A brick wall is a flat face made of identical rectangles. Each brick, together with its share of the mortar joint, takes up one small rectangle on that face. Divide the wall area by the area of that rectangle and you have the number of bricks. That is the idea behind every good brick wall calculator, and it is also how a hand brickwork calculation for a wall is done.
You give the calculator the wall length and height (or a total area), any openings, the brick face size, the mortar joint, the number of wythes, which are the layers of brick across the thickness of the wall, and a waste percentage. The tool works out the net wall area, finds the area of one brick plus its joint, divides, multiplies by the number of wythes, then adds waste and rounds up.
The results are the net wall area, bricks per square foot or square meter, net bricks, and bricks to order. If you switch on the mortar estimate you also get the mortar volume and either premixed bags or cement and sand, and if you enter prices you get an estimated cost. A diagram shows your brick and joint to scale, and a step-by-step block shows every line of the math.
The count assumes running bond with even bed and head joints, and the same joint on every side of the brick. Arches, soldier courses, decorative patterns, and heavy cutting at corners can raise the real figure, which is what the waste field is for. Collar joints between wythes are ignored. Foundations, lintels, wall ties, and labor are not included. The result is a planning estimate, not a structural design.
2. How to Use the Brick Calculator
- Choose imperial or metric units, and choose whether to enter each wall as length and height or as a total area.
- Enter the length and height of your first wall, or its area.
- Add doors, windows, or other openings to that wall with their width, height, and quantity.
- Use Add Another Wall for each extra wall in the project.
- Pick a brick size from the list, or choose Custom and enter your own. For a custom size, say whether your numbers are specified (actual) or nominal.
- Check the mortar joint and set the wall thickness in wythes.
- Set your waste allowance.
- Optionally switch on the mortar estimate and enter prices to see quantities and cost.
- Review the bricks to buy, the materials list, and the step-by-step math. Use Copy Result, Share Result, or Download PDF to keep the numbers, and Reset All to start again.
You can add up to 6 walls and up to 8 openings on each wall. If a number is outside the allowed range, the calculator tells you and uses the nearest allowed value instead of changing it silently. If a required field is blank, it asks for the value instead of guessing.
3. Brick Calculator Formula
Bricks per area = 1 / ((l + t) x (h + t))
Here l is the brick face length, h is the brick face height, and t is the mortar joint. For bricks per square foot, use inches and divide 144 by the module area in square inches.
Net wall area = (Length x Height) - Opening area
Net bricks = Net wall area x Bricks per area x Wythes
Bricks to order = rounded-up (Net bricks x (1 + Waste %))
The calculator rounds up only at the end, never in the middle of the calculation.
For a bricks calculation formula in feet, convert every brick measurement to inches first, because one square foot is 144 square inches. Keep the units the same on both sides of every step.
The mortar estimate uses the volume of the joints around each brick:
Joint mortar per brick = w x [ (l + t)(h + t) - l x h ]
Mortar to order = Net bricks x Joint mortar per brick x (1 + Allowance %)
Here w is the brick width. For cement and sand mortar, the dry volume is the mortar volume times 1.33, split by your mix ratio.
4. Worked Examples
US garden room wall
These are the calculator's default values. The wall is 20 ft long and 8 ft high, with a door opening 3 ft wide by 7 ft high and a window 3 ft by 4 ft. The brick is US Modular (7-5/8 by 2-1/4 inch face), the joint is 3/8 inch, there is one wythe, and waste is 10%.
| Step | Calculation | Result |
|---|---|---|
| Gross area | 20 x 8 | 160 sq ft |
| Openings | (3 x 7) + (3 x 4) | 33 sq ft |
| Net area | 160 - 33 | 127 sq ft |
| Brick plus joint | (7.625 + 0.375) x (2.25 + 0.375) | 21 sq in |
| Bricks per sq ft | 144 / 21 | 6.857 |
| Net bricks | 127 x 6.857 | 870.9, so 871 |
| Bricks to order | 870.9 x 1.10 = 958.0 | 958 bricks |
For the mortar, one brick has 3.625 x (21 - 7.625 x 2.25) = 13.93 cubic inches of joint around it. Across 870.9 bricks that is about 7.02 cubic feet of wet mortar. With a 25% allowance it is 8.78 cubic feet. At a typical 0.6 cubic feet per bag, that is 14.6 bags, so buy 15 bags. If you mix your own at 1:4, the dry volume is 11.7 cubic feet, which is about 2.3 cubic feet of cement and 9.3 cubic feet of sand.
Metric boundary wall
A boundary wall is 12 m long and 2.4 m high with a gate 3 m by 2.1 m. The brick is a South Asian red brick, 230 by 75 mm on the face and 115 mm wide, with 10 mm joints. The wall is 9 inches thick, which is two wythes, and waste is 5%.
- Net area = 28.8 - 6.3 = 22.5 sq m
- Brick plus joint = 0.240 x 0.085 = 0.0204 sq m, so 49.02 bricks per sq m per wythe
- Net bricks = 22.5 x 49.02 x 2 = 2,205.9, so 2,206 bricks
- Order with 5% waste = 2,205.9 x 1.05 = 2,316.2, so 2,317 bricks
- Wet mortar is about 0.80 cubic meters, 1.00 with a 25% allowance, and 1.33 dry. In a 1:5 mix that is about 0.22 cubic meters of cement (roughly 319 kg, or 7 bags of 50 kg) and 1.1 cubic meters of sand.
5. Understanding Your Result
The net bricks figure is what the wall needs if every brick fits and none breaks. The bricks to order figure is what you should buy. Neither number is exact, because real walls have cuts at corners and openings, and bricks vary in size from batch to batch.
Round only at the end. Rounding the bricks per square foot to 7 early can add dozens of bricks on a large wall. Then round up to whole packs, since most suppliers sell bricks by the pack, cube, or pallet. Ask what quantity they supply and whether leftovers can be returned.
If a supplier's quote is far from the calculator, check the brick size basis and the number of wythes first. Those two inputs cause most of the gap.
6. Mortar Estimate for Brickwork
The mortar section works as a brick and mortar calculator. It finds the joint volume around every brick, adds an allowance for droppings and uneven beds, and converts the total to bags or to cement and sand. A useful rule of thumb is that 1,000 modular bricks with 3/8 inch joints need about 8 cubic feet of mortar in the joints, and roughly 10 cubic feet once the allowance is added.
Premixed bags vary by brand, so replace the default yield with the figure printed on your bag. For cement and sand mortar, the calculator multiplies the wet volume by 1.33 to get dry materials, then splits that volume by your mix ratio. It treats a 94 lb bag of cement as about one cubic foot, and a 50 kg bag as about 0.035 cubic meters. Common mixes such as 1:4 for general masonry and 1:5 or 1:6 for lighter work are only starting points, because your mason or local code decides the right mix.
7. Brick Sizes and Bricks per Square Foot
Brick measurements are a frequent source of mistakes. A brick has a specified size, which is the size of the unit itself, and a nominal size, which is the specified size plus a joint. A modular brick with a specified length of 7-5/8 inches and a 3/8 inch joint has a nominal length of 8 inches. The Brick Industry Association covers modular and non-modular dimensioning and estimating in Technical Note 10, Dimensioning and Estimating Brick Masonry. If you type a nominal size into a calculator that also adds a joint, the joint is counted twice and the result comes out too low. The calculator lets you mark a custom size as nominal so it takes the joint out first.
The first table comes from the formula above with a 3/8 inch joint and a single wythe.
| Brick | Face size (length x height) | Bricks per sq ft | Per 100 sq ft |
|---|---|---|---|
| Modular | 7-5/8 x 2-1/4 in | 6.86 | 686 |
| Standard | 8 x 2-1/4 in | 6.55 | 655 |
| Engineer Modular | 7-5/8 x 2-3/4 in | 5.76 | 576 |
| King | 9-5/8 x 2-5/8 in | 4.80 | 480 |
| Norman | 11-5/8 x 2-1/4 in | 4.57 | 457 |
| Utility | 11-5/8 x 3-5/8 in | 3.00 | 300 |
For metric work with a 10 mm joint and one wythe:
| Brick | Face size | Bricks per sq m |
|---|---|---|
| South Asian red brick | 230 x 75 mm | 49.02 |
| Australian | 230 x 76 mm | 48.45 |
| Metric modular | 190 x 90 mm | 50.00 |
| UK | 215 x 65 mm | 59.26 |
Multiply by the number of wythes for thicker walls. The reference tab under the calculator shows the same figures for all ten presets and updates with your own joint and wall thickness.
8. Wall Thickness and Wythes
A wythe is one vertical layer of brick. A half-brick wall, about 4 inches thick with US brick, is one wythe. A one-brick wall, often called a 9 inch wall in South Asia, is two wythes, so it needs about twice the bricks for the same face area. A one-and-a-half brick wall is three wythes. The calculator multiplies the face count by this number, which is a close planning estimate for most bonds.
Thicker walls use header courses, ties, or a collar joint between wythes, and the cutting pattern can change the real figure slightly. If your design uses a special bond, ask your mason for a count and use the waste field to match it.
9. Units and Conversions
- 1 foot = 12 inches, and 1 square foot = 144 square inches
- 1 inch = 25.4 millimeters
- 1 square meter = 10.7639 square feet
- 1 cubic foot = 0.0283 cubic meters, or about 28.3 liters
- 1 cubic yard = 27 cubic feet
Do not mix inches and millimeters in one set of numbers. The unit switch converts your entries when you change systems and keeps the original precision, but a number typed in the wrong system is still wrong.
10. Practical Tips
- Measure a few real bricks rather than trusting a catalog size. Hand-made and reclaimed bricks vary the most.
- Confirm the joint thickness with whoever is laying the brick. A 1/2 inch joint instead of 3/8 inch lowers the count noticeably.
- Use about 5% waste for a plain straight wall, around 10% for typical work, and 15% when there are many corners, openings, or cut bricks. Treat these as planning figures and ask your supplier.
- Order all the bricks for a wall at once. Colors can shift between production batches.
- Keep brick and mortar quantities separate from labor. This calculator does not price labor, scaffolding, ties, lintels, or foundations.
- Run the numbers again with the final supplier size before you place the order.
11. Common Mistakes
- Adding the joint to a nominal size. Nominal sizes already include the joint.
- Forgetting the second wythe on a 9 inch or boundary wall.
- Mixing units, such as a wall in feet and a brick in millimeters.
- Skipping openings, or subtracting a shared door from two walls.
- Rounding bricks per square foot to 7 for a big wall and ending up with a large overage.
- Leaving out foundation courses or a plinth that sits below ground level.
- Using the net count as the order. The net count has no breakage allowance.
12. Related Calculations and Use Cases
The same method answers a lot of different questions. A boundary wall brick calculator is just a long, low wall with a gate to subtract and usually two wythes. A brick calculator for a house means adding every wall and opening on separate wall cards, and a red brick calculator is the same calculation with a red clay brick size such as the South Asian preset. For a brick wall cost calculator, enter your price per brick and mortar prices and read the estimated cost.
For flat brickwork, such as a patio or floor, enter the exposed face as the brick length and width, enter the surface area using the total area option, and set one wythe. This is a simplified area count. It does not include edge restraint, bedding sand, base material, or pattern cutting, and a herringbone layout needs more waste than a straight pattern.
If your wall is built with concrete masonry units instead of clay brick, such as a foundation or backing wall, use our Concrete Block Calculator, which handles block face sizes and grout fill.
13. Frequently Asked Questions
With a 3/8 inch mortar joint, a modular brick (7-5/8 by 2-1/4 inch face) works out to about 6.86 bricks per square foot of single-wythe wall, and a standard brick (8 by 2-1/4 inch face) to about 6.55. Larger faces need fewer, for example about 4.80 for a king brick. In metric, a 230 by 75 mm face with a 10 mm joint gives about 49 bricks per square meter. These are net counts before waste.
Multiply the wall length by the height to get the gross area, then subtract the area of each door and window. Divide the remaining area by the area of one brick plus its mortar joint, which is (brick length + joint) times (brick height + joint). Multiply by the number of wythes, add waste, and round up. The calculator above does these steps for every wall and opening you enter.
A common planning allowance is 5 to 10 percent for a simple straight wall, and 10 to 15 percent when there are many corners, openings, or cut bricks. The calculator defaults to 10 percent and lets you change it. Your mason or supplier may suggest a different figure for your bond and brick type.
A 9 inch (one-brick-thick) wall has two wythes, so it needs about twice the bricks of a half-brick wall with the same face area. Set the wall thickness to 2 wythes, enter the length and height, and add any gate as an opening. For a wall 12 m long and 2.4 m high with a 3 m by 2.1 m gate, 230 by 75 mm bricks, and 10 mm joints, the net count is about 2,206 bricks.
For modular brick with 3/8 inch joints, the joints hold about 8 cubic feet of mortar per 1,000 bricks, and about 10 cubic feet once you allow roughly 25 percent for waste and droppings. For 1,000 bricks of 230 by 115 by 75 mm with 10 mm joints, that is about 0.36 cubic meters in the joints, or about 0.45 with the allowance. Premixed bag yields differ, so check the label.
Conclusion
This brick calculator turns a wall size into a practical shopping list. It subtracts openings, divides the net area by the area of one brick and its joint, multiplies by the number of wythes, and adds waste so you buy enough. Accurate inputs matter most, especially the real brick size, the joint thickness, and the wall thickness. Use the mortar and cost options to plan the whole job, and confirm the final quantities with your supplier or mason before you order. A few minutes with the calculator can prevent a short delivery, a mismatched second batch, or a pile of leftover bricks.
This calculator is for planning purposes only. Brick size, wall thickness, and mortar mix must follow your plans, supplier data, and local building code. Confirm all quantities with your supplier or mason before ordering.