Concrete blocks, also known as concrete masonry units, cinder blocks and breeze blocks, come in a number of sizes, depending on the country of origin. Standard U.S. blocks, used throughout most of the world, are 16 inches long by 8 inches wide by 8 inches tall.
The U.K. standard for blocks is smaller, measuring 17.3 inches long by 8.5 inches tall by 3.9 inches wide. New Zealand standard block sizes are smaller yet, measuring 15.4 inches long by 7.5 inches tall by 7.5 inches wide.
Concrete blocks are often used in combination with steel reinforcing bars to form reinforced concrete block structures used as load-bearing columns, beams and walls.