Brick Calculator
Work out how many bricks a single-wythe wall needs, mortar joints included.
Last reviewed September 19, 2026
Result
Enter wall length and wall height to see the result.
https://calcgallery.com/masonry/brick-calculator/
Results are estimates for planning only. Actual needs vary with site conditions, products and workmanship. Always confirm quantities with your supplier and follow local building codes and manufacturer instructions. Read the full disclaimer
How to use it
- Measure the wall length and height.
- Enter the total area of any doors or windows so they come out of the count.
- Check the brick size and mortar joint. Both are filled in for your region and both matter.
- Read the brick count. It is for a single-wythe wall, one brick thick.
How it is calculated
Each brick occupies its face size plus one mortar joint on each of two edges:
Bricks per area = 1 ÷ ((face length + joint) × (face height + joint))
Bricks = ceil(net wall area × that × (1 + waste))Net wall area is the wall minus any openings.
Brick sizes differ by market and this uses the one for your region: a US modular brick with a 3/8 in joint, or a UK standard brick with a 10 mm joint. Both are editable, because specials and imports do not follow either.
This is a single-wythe wall throughout. Anything thicker is a multiple of this count, and a cavity wall is two leaves plus ties.
Practical tips
Order a full pack over. Bricks come in packs and a part pack is awkward to buy later. Matching a discontinued or re-fired brick a year on is close to impossible, so a spare pack in the garage is cheap insurance against a damaged wall.
Check the batch. Clay bricks vary in colour between firings. Mixing packs as you lay, rather than working through one pack at a time, spreads any variation across the wall instead of leaving a visible block of it.
Dry-lay the first course. Setting out the bottom course without mortar shows where the perpends fall and whether you finish on a whole brick. Adjusting the joint by a millimetre or two over a run is much easier than cutting every brick at one end.
Keep the bricks dry before laying, and damp when you lay. Soaked bricks float on the mortar and the wall moves. Bone-dry bricks in hot weather suck the water out of the mortar before it cures. Both weaken the joint.
Anything structural needs more than a brick count. Foundations, wall ties, movement joints, lintels and height limits are all regulated and vary locally. This works out how many bricks. It does not tell you whether the wall will stand up.
With your numbers
- Each brick occupies (7.625 in + 0.375 in) × (2.25 in + joint)
- That is 6.857 bricks per square foot
- Wall = 100 ft², so 686 bricks
- With 5% waste = 720 bricks
Quick reference
Bricks at openings and corners get cut, and some arrive broken, so this includes 5% extra.
| Job | Bricks to buy |
|---|---|
| 10 × 8 ft wall, no openings | 576 |
| 10 × 10 ft wall, no openings | 720 |
| 20 × 6 ft garden wall | 864 |
| 20 × 8 ft wall with a 20 ft² opening | 1,008 |
| 4 × 2.5 m wall, no openings | 623 |
| 6 × 2 m garden wall | 747 |
| 8 × 2.4 m wall with a 2 m² opening | 1,071 |
Common questions
- How many bricks per square foot?
- About 6.86 for a US modular brick with a 3/8 in joint, single wythe. For a UK standard brick with a 10 mm joint it is about 60 per square metre. Both are calculated above from the sizes, not quoted from memory.
- Does this cover a double-wythe wall?
- No. This is single wythe, one brick thick. A double-wythe wall is twice this count, and a cavity wall is two separate leaves with ties, which is a different job with different requirements.
- Why does the mortar joint change the count?
- Because each brick occupies its own size plus one joint on each of two edges. A 3/8 in joint on a 7.625 in brick adds 5%, and over a whole wall that is dozens of bricks.
- Should I subtract windows and doors?
- Yes, and there is a field for it. On a wall with a large opening, not subtracting it can overstate the count by a fifth.
- How much mortar will I need?
- This does not estimate mortar, because there is no reliable figure that survives different joint sizes, brick absorbency and how much ends up on the ground. Ask your supplier, who will know for the brick you are buying.
- Why 5% waste and not 10%?
- Bricks are cut at openings and corners and a few arrive broken, but unlike tile the offcuts are often usable elsewhere in the wall. Five percent is the usual trade allowance.