Brick & Block Calculator

Concrete & masonryFree calculator

Calculate how many bricks or concrete blocks you need for a wall, and how much mortar. Choose your brick or block size, subtract any openings and get a full shopping list.

Your shopping list

How to measure

  1. Measure the length and height of the wall.
  2. Measure any windows, doors or gaps and add up their area.
  3. Choose the brick or block size you plan to use.

The formula

Wall area = length × height − openings
Bricks = wall area × bricks per unit area × (1 + waste %)
US modular brick ≈ 6.86 per sq ft · UK brick ≈ 60 per m² · block ≈ 10 per m²

Worked example

A 20 ft × 4 ft garden wall is 80 sq ft. With modular bricks at 6.86 per sq ft and 5% waste you need 577 bricks and about 15 bags of mortar mix.

Tips before you buy

  • These figures are for a single-skin (half-brick) wall. Double them for a double-skin wall.
  • Order 5–10% extra to allow for breakages and cuts.
  • Walls over about 3 ft (1 m) high may need foundations and building approval.

Frequently asked questions

How many bricks in a square metre?

About 60 standard UK bricks (215 × 65 mm) per m² with 10 mm mortar joints, for a single-skin wall.

How many bricks per square foot?

About 6.86 US modular bricks per sq ft with 3/8 in joints.

How much mortar per 1,000 bricks?

Roughly 7 bags of masonry cement plus sand, or about 25 bags of 80 lb pre-mixed mortar.

Results are estimates for planning only. Always check quantities with your supplier before you buy.