How many bricks do I need? How to use the calculator
- 1Enter the wall's length and height, and take off doors and windows.
- 2Choose single or double skin.
- 3Pick your brick or block, or enter a custom size with its joint.
How to calculate bricks and mortar (formula)
- 01Units per m² = 1 ÷ ((length + head joint) × (height + bed joint))
- 02Units = units per m² × wall area × skins × (1 + extra %), rounded up
- 03Joints ≈ wall area × skins × depth × (1 − face area ÷ (face area with joints))
- 04Mortar = (joints + joints between skins + filled frogs) × (1 + extra %)
- 05Dry mix = mortar × 1.33 · cement = dry mix × 1 ÷ (1 + sand parts) × 1,440 kg/m³ · sand = the rest
- 06Brickwork volume = wall area × (skins × depth + joints between skins)
A UK brick (215 × 65 mm) with 10 mm joints takes 225 × 75 mm of wall, which is 59.3 bricks per m² — the trade's "60 a metre". A 440 × 215 mm block is 9.9 per m², so "10 a metre".
A US modular brick with 3/8 in joints is 6.86 bricks per ft², and a standard CMU block is 1.125 per ft².
Pakistan's PWD Schedule of Rates gives the traditional brick as 9 × 4⅜ × 2 11/16 in with joints of at most ⅜ in: 5.02 bricks per ft² of each skin, or 13.4 per cubic foot of 9 in brickwork measured at its nominal 9 in — the familiar "13½ bricks per cft". India's modular brick (IS 1077, 190 × 90 × 90 mm) is 50 per m² per skin, the Australian standard brick 48.5 per m², and a 400 × 200 mm block (390 × 190 mm actual, IS 2185) 12.5 per m².
The mortar starts from the volume of the joints. India's CPWD analysis of rates allows 0.22 m³ of mortar per m³ of modular brickwork, where the joints themselves are about 0.19 m³, so the calculator adds 15 % for droppings and fuller joints. Bricks laid frog up (the PWD way in Pakistan) also fill their frogs.
Brick calculation example
A 5 m × 2 m single-skin wall is 10 m². UK bricks with 10 mm joints need 59.26 per m².
With 5% extra, buy 623 bricks. Mortar: about 203 L.
Mixed 1 : 4, that mortar takes 2 bags of cement (78 kg) and 0.22 m³ of sand.
How many bricks per square metre?
| Brick or block | Per m², half-brick wall | Per m², one-brick wall | Per 100 ft², single leaf |
|---|---|---|---|
| UK standard brick 215 × 102.5 × 65 mm | 59.3 | 118.5 | 551 |
| US modular brick 7⅝ × 3⅝ × 2¼ in | 73.8 | 147.6 | 686 |
| German NF brick 240 × 115 × 71 mm | 48.2 | 96.4 | 448 |
| Dutch waal format 210 × 100 × 50 mm | 75.8 | 151.5 | 704 |
| Pakistani brick 9 × 4⅜ × 2 11/16 in (228 × 111 × 68 mm) | 54 | 108 | 502 |
| Indian modular brick 190 × 90 × 90 mm | 50 | 100 | 465 |
| Australian standard brick 230 × 110 × 76 mm | 48.4 | 96.9 | 450 |
| UK concrete block 440 × 215 × 100 mm | 9.9 | 19.8 | 92 |
| US concrete block (CMU) 15⅝ × 7⅝ × 7⅝ in | 12.1 | 24.2 | 113 |
| French concrete block (parpaing) 500 × 200 × 200 mm | 9.3 | 18.7 | 87 |
| Concrete block 400 × 200 × 100 mm (390 × 190 actual) – South Asia, Gulf | 12.5 | 25 | 116 |
| Concrete block 400 × 200 × 150 mm (390 × 190 actual) – South Asia, Gulf | 12.5 | 25 | 116 |
| Concrete block 400 × 200 × 200 mm (390 × 190 actual) – South Asia, Gulf | 12.5 | 25 | 116 |
| Australian concrete block 390 × 190 × 190 mm | 12.5 | 25 | 116 |
With each size's usual joints (10 mm; ⅜ in in the US and Pakistan; 12 mm bed joints for German NF), before any spare for cutting and breakage.
Tips before you buy
- Buy bricks from one batch, and mix bricks from several packs as you lay to avoid colour bands.
- Keep bricks and blocks off the ground and covered before use.
- Wear gloves and eye protection when cutting bricks or handling cement.
Frequently asked questions
How many bricks per square metre?
About 60 for UK standard bricks in a single-skin wall, and 120 for a double-skin (one-brick) wall.
How many blocks per square metre?
About 10 standard 440 × 215 mm blocks.
How many bricks per square foot?
About 6.9 US modular bricks with 3/8 in joints.
How many bricks are in a cubic foot of brickwork in Pakistan?
About 13½ for the traditional 9 × 4⅜ × 2 11/16 in brick with ⅜ in joints: a 9 in wall has 10.03 bricks per ft² of face, and 10.03 ÷ 0.75 ft = 13.4 per cubic foot. Choose the Pakistani brick and a double-skin (9 in) wall.
How much cement and sand do I need for brickwork?
Choose your mortar mix and cement bag. The calculator takes the wet mortar, multiplies it by 1.33 for the dry materials and splits that by the mix: at 1 : 6 one part in seven is cement (1,440 kg per m³) and six are sand.
Sources
- Standard sizes: UK brick 215 × 102.5 × 65 mm and block 440 × 215 mm with 10 mm joints; US modular brick and CMU with 3/8 in joints.
- Pakistan PWD Schedule of Rates 2022, specifications: brick sizes (traditional 9 × 4⅜ × 2 11/16 in), joints ≤ ⅜ in, bricks laid frog on top, mortar 1:4–1:8
- IS 1077:1992 common burnt clay building bricks: modular 190 × 90 × 90 mm; frogs 10–20 mm deep
- IS 2185 (Part 1):2005 concrete masonry units: nominal sizes include the 10 mm joint (400 × 200 mm = 390 × 190 mm)
- CPWD Analysis of Rates 2012, Vol. 1: 0.22 m³ mortar per m³ of modular brickwork; 1:4 mortar = 0.268 m³ cement + 1.07 m³ sand per m³
- PGH Bricks brick calculator: Australian standard brick 230 × 110 × 76 mm, 48.5 per m²
- Austral Masonry: 20.01 full block 390 × 190 × 190 mm
- Forterra, London Brick technical data sheet: frogged, 15–20 % voids
Formulas last reviewed: September 30, 2026 ·How we check our formulas