acalculator

How many bricks do I need?

Type the wall’s length and height, the area of any doors and windows, and pick the brick size and mortar joint. The brick calculator counts the bricks to buy, with waste and an optional cost.

Your numbers

Units
Bricks to buy
576

You need 576 bricks (6.857 bricks per square foot).

Bricks without waste
548.6
Bricks per square foot
6.857
Bricks per square metre
73.81
Net wall area
80 ft²

Bricks to buy: 576. You need 576 bricks (6.857 bricks per square foot).

How to calculate

Brick calculator: how many bricks a wall needs from its length and height, less doors and windows, for US modular, UK or your own brick size with its mortar joint, plus waste and cost.

Example with the default inputs (Wall length 10 ft, Wall height 8 ft, Brick size US modular, 7 5/8 × 2 1/4 in, Mortar joint 0.375 in, Waste 5%): You need 576 bricks (6.857 bricks per square foot).

Method: Bricks = (length × height − openings) × (1 + waste ÷ 100) ÷ ((brick length + joint) × (brick height + joint)), rounded up.

  • One layer of brick (a single wythe) laid in running bond; each brick fills its face plus one joint.
  • US modular brick is 7 5/8 × 2 1/4 in on its face; UK standard brick 215 × 65 mm.
  • Waste is 5% by default for cuts and breakage.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Wall length 10 ft, Wall height 8 ft, Brick size US modular, 7 5/8 × 2 1/4 in, Mortar joint 0.375 in, Waste 5% gives Bricks to buy 576, Bricks per square foot 6.857143, Bricks without waste 548.571429.Source: Wikipedia, Brick (US modular brick 7 5/8 × 3 5/8 × 2 1/4 in; UK brick 215 × 102.5 × 65 mm with a nominal 10 mm joint), https://en.wikipedia.org/wiki/Brick (retrieved 2026-10-03)
  2. Wall length 16.4 ft, Wall height 6.562 ft, Brick size UK standard, 215 × 65 mm, Mortar joint 0.3937 in, Waste 0%, Price per brick $0.60 gives Bricks to buy 593, Bricks per square metre 59.259259, Cost $355.80.Source: Wikipedia, Brick (US modular brick 7 5/8 × 3 5/8 × 2 1/4 in; UK brick 215 × 102.5 × 65 mm with a nominal 10 mm joint), https://en.wikipedia.org/wiki/Brick (retrieved 2026-10-03)
  3. Wall length 20 ft, Wall height 8 ft, Doors and windows 21 ft², Brick size Other: type the brick size, Brick length 8 in, Brick height 2.25 in, Mortar joint 0.5 in, Waste 10% gives Net wall area 139 ft², Bricks to buy 942.

How it works

Each brick, with its mortar joint, covers a face of (brick length + joint) × (brick height + joint). Then:

  • Net wall area = wall length × wall height − doors and windows.
  • Bricks without waste = net wall area ÷ that face.
  • Bricks to buy = bricks without waste × (1 + waste ÷ 100), rounded up to a whole brick.
  • Bricks per square foot = 1 ft² (0.09290304 m²) ÷ the face; bricks per square metre = 1 m² ÷ the face.
  • Cost = bricks to buy × the price per brick, when you type a price.

Brick sizes (face as laid). US modular 7 5/8 × 2 1/4 in (193.675 × 57.15 mm); UK standard 215 × 65 mm; or a length and height you type. The joint defaults to 3/8 in.

Rules

  • Wall length and height are more than 0 and at most 10 km; brick sizes 1 mm to 1 m; the joint 0 to 100 mm; waste 0 to 100%.
  • If the doors and windows are as large as the wall or larger, there is no answer: "The doors and windows take up the whole wall."

Output format

Bricks to buy is a whole number. Bricks without waste shows to 1 decimal, per square foot to 3, per square metre to 2, the net area in ft² (US) or m² (Metric) to 2, and the cost in money. All sizes are read back as the exact decimals you typed, every step is exact, and the count is rounded up only once: 80 ft² of modular brick with 5% waste is exactly 576, not 577.

Worked examples by hand

A 10 × 8 ft wall of modular brick, 3/8 in joints, 5% waste. Face: (7.625 + 0.375) × (2.25 + 0.375) = 8 × 2.625 = 21 in². Per ft²: 144 ÷ 21 = 6.857. Wall: 80 ft² × 6.857 = 548.57 bricks. With waste: 548.57 × 1.05 = 576 exactly, so 576 bricks.

A 5 × 2 m wall of UK brick, 10 mm joints, no waste, £0.60 each. Face: 225 × 75 mm = 0.016875 m². Per m²: 59.26. Wall: 10 m² ÷ 0.016875 = 592.59, so 593 bricks. Cost: 593 × 0.60 = 355.80.

A 20 × 8 ft wall with 21 ft² of openings, 8 × 2 1/4 in brick, 1/2 in joints, 10% waste. Face: 8.5 × 2.75 = 23.375 in². Net area: 160 − 21 = 139 ft². Bricks: 139 × 144 ÷ 23.375 = 856.30; × 1.1 = 941.93, so 942.

Other questions people ask

How many bricks are in a square foot?

About 6.86 US modular bricks. A modular brick is 7 5/8 × 2 1/4 in on its face; with a 3/8 in joint each one takes 8 × 2 5/8 = 21 in², and 144 ÷ 21 = 6.857.

How many bricks are in a square metre?

About 59.3 UK bricks. A 215 × 65 mm brick with a 10 mm joint takes 225 × 75 mm = 0.016875 m², and 1 ÷ 0.016875 = 59.26.

How do I work out how many bricks I need?

Multiply the wall length by the height, take away doors and windows, and divide by the face of one brick plus one joint in each direction. Add 5 to 10% for cuts and breakage and round up.

How many bricks do I need for a 10 × 8 ft wall?

With modular brick and 3/8 in joints, 80 ft² × 6.857 = 548.57 bricks, or 576 with 5% waste (548.57 × 1.05, rounded up once).

Does the mortar joint change the count?

Yes. A thicker joint makes each brick cover more wall, so you need fewer bricks. Use the joint your mason lays: 3/8 in is usual in the US and 10 mm in the UK.

Is this for a single or double wall?

A single layer (one wythe) of brick. For a double wall, double the count.