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Block Calculator

Blocks, mortar, courses — the masonry order in one pass.

Masonry counts are coverage math: one standard 8×8×16 block shows 0.889 sq ft of face. This calculator converts your wall dimensions to a block count with 5% breakage, mortar at ~3 bags per 100 blocks, and the course count — the same numbers a mason writes on the order.

Why people use this

Anyone pricing a garden wall or foundation uses this: block-per-square-foot is simple, but the breakage factor and mortar ratio are where orders come up short mid-wall. The per-block labor field doubles as a check against a mason's quote.

How it works

1. Enter wall length and height in feet.
2. Read the block count (breakage included), mortar bags, and courses.
3. Open the cost section for per-block, mortar, and laying-labor rates.

Common questions

How many concrete blocks per square foot of wall?

1.125 blocks per square foot for standard 8×8×16 units (each shows 0.889 sq ft of face). A 40×4 ft wall is 160 sq ft = 180 blocks, or 189 with 5% breakage.

When does a block wall need rebar and grout?

Generally any wall over 4 feet, any retaining wall, and anything structural — vertical rebar in grout-filled cells every 32–48 inches is the common code pattern, with footings sized to the soil. Check your local code before laying the first course.

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