Brick Calculator

A brick calculator returns the bricks and 80 lb mortar bags a wall needs. It works out bricks per square foot from the brick face size plus the mortar joint, multiplies by wall area, adds waste, and rounds up. Mortar bags use a published yield of about 37 standard bricks per bag.

Last reviewed September 2026Method & sources Report an error

Not to scale.

Bricks Needed

1,152

Includes a 5% waste allowance.

Shopping list

Bricks1,152 bricks
Mortar mix32 80 lb bags

Breakdown
Bricks Needed	1,152
Mortar Mix Bags (80 lb)	32
Bricks per Sq Ft	6.86
Wall Area	160 sq ft

How to Calculate Brick

A brick's actual face size plus the mortar joint on two sides gives its nominal size. This is the footprint it actually occupies in the wall, joint included. Dividing 144 sq in. (1 sq ft) by that nominal face area gives bricks per sq ft. Multiplying by wall area and adding a waste allowance for cuts and breakage gives the brick count, rounded up to a whole brick. QUIKRETE's Mortar Mix No. 1102 data sheet states one 80 lb bag lays about 37 standard bricks. Divide the brick count by that figure and round up to get the mortar bags needed.

Example: 20 ft × 8 ft wall, standard modular brick (7.625 in. × 2.25 in. face)

A 20 ft × 8 ft wall, standard modular brick (7.625 in. × 2.25 in. face), 3/8 in. (0.375 in.) mortar joints, 5% waste: 1. Wall area: 20 × 8 = 160 sq ft 2. Nominal size: (7.625 + 0.375) × (2.25 + 0.375) = 8.0 × 2.625 = 21 sq in. 3. Bricks per sq ft: 144 ÷ 21 = 6.86 4. Raw bricks needed: 160 × (144 ÷ 21) = 1,097.1 5. With 5% waste: 1,097.1 × 1.05 = 1,152 bricks 6. Mortar bags: 1,152 ÷ 37 = 31.14, rounded up to 32 bags

Brick: Compare Scenarios

Scenario	Bricks Needed	Mortar Mix Bags (80 lb)	Bricks per Sq Ft	Wall Area
Small (10×4 ft accent wall)	288	8	6.86	40 sq ft
Medium (20×8 ft wall)	1,152	32	6.86	160 sq ft
Large (40×16 ft two-story wall)	4,608	125	6.86	640 sq ft

What Is Brick?

A brick calculator converts a wall's dimensions into the number of bricks and mortar bags needed. It derives bricks-per-square-foot directly from the brick's actual dimensions and mortar joint width rather than assuming one fixed brick size. Brick sizes vary meaningfully. Modular, queen, king, and other formats all have different nominal face sizes, and joint width itself can vary by design.

Brick: Pros and Cons

Pros

Derives bricks-per-square-foot from actual brick and joint dimensions instead of a single fixed industry constant, since real brick formats (modular, queen, king, and others) genuinely differ in size
Mortar bag yield is grounded in a real manufacturer data sheet (QUIKRETE Mortar Mix No. 1102), the same figure used in the Block Mortar calculator
Works for any joint width, not just the common 3/8 in. standard

Cons

Doesn't account for a header course or other bonding pattern that uses brick differently than a simple running bond. A Flemish or English bond pattern uses more brick per sq ft than assumed here.
Doesn't determine wall thickness or whether the brick is structural or a veneer. That's a separate design decision outside this calculator's material-quantity scope.
Assumes a single uniform wall. Openings (doors, windows) should be subtracted from the wall area before entering it, since brick doesn't go over an opening

Brick: What a Pro Checks

Mortar bag count assumes a simple running bond. A Flemish, English, or other bond pattern with a header course uses more brick per sq ft, so budget extra for those patterns.
Measure your actual mortar joint width before ordering. A wider joint means each brick occupies more nominal wall area, which changes both the brick count and the mortar bag count.
Confirm your bag yield against the product you're actually buying. This estimate uses QUIKRETE's published figure of about 37 bricks per 80 lb bag of Mortar Mix No. 1102. A different mortar product can yield differently.
Subtract door and window openings from the wall area before entering it. Brick doesn't go over an opening, and this estimate doesn't remove them automatically.

Frequently Asked Questions

How many bricks do I need per square foot?

It depends on the brick's exact size and mortar joint width, but a standard modular brick (7-5/8 in. × 2-1/4 in. face) with 3/8 in. joints works out to about 6.86 bricks per sq ft. A larger brick format needs fewer per sq ft. A narrower joint needs slightly more.

How many bags of mortar do I need for a brick wall?

Per QUIKRETE's Mortar Mix No. 1102 data sheet, one 80 lb bag lays about 37 standard bricks. Divide your total brick count by 37 and round up. For 1,152 bricks, that's 32 bags.

What is the standard size of a brick?

"Modular" brick, the most common US residential format, has an actual face size of about 7-5/8 in. × 2-1/4 in. With a 3/8 in. mortar joint, that gives an 8 in. × 2-5/8 in. nominal face, about 6.86 bricks per sq ft. Some published tables list a 2-2/3 in. nominal height instead, which works out to about 6.75 bricks per sq ft, roughly 2 percent fewer. Enter the joint you actually lay to match your wall. Other formats (queen, king, Norman, and more) use different actual and nominal dimensions.

How much waste should I plan for a brick project?

5% is a reasonable default for a straightforward wall. A project with a lot of cuts around openings, corners, or a more complex bond pattern should plan for more, closer to 10-15%.

Does mortar joint width really change how many bricks I need?

Yes, meaningfully. A wider mortar joint means each brick occupies more nominal wall area, so fewer bricks (but proportionally more mortar) are needed to cover the same wall. This calculator derives that relationship directly from your joint width input rather than assuming one fixed joint size.

Sources

QUIKRETE Mortar Mix No. 1102 Data Sheet (bricks laid per 80 lb bag) (opens in a new tab)

Siding