Concrete Block Calculator

Calculate the number of concrete blocks needed.

How It Works

Blocks = ceil(Wall area ÷ (16 × 8 ÷ 144)) = ceil(Area × 1.125).

Example

A 20 ft × 8 ft wall needs 180 standard 8x8x16 blocks.

Frequently Asked Questions

What size is a standard block?

The nominal 8x8x16 block has a 16 × 8 in face and covers 0.89 sq ft per block.

Do all block widths use the same face?

Yes — 4, 8, and 12 in blocks share the same 16 × 8 face, so block count is identical.

Should I add for waste?

Add 5% for cuts and damage; more for walls with many openings.