Small garden wall
Simple block and mortar count.
117 blocksConcrete blocksconcrete block estimator
Concrete Block Estimator
A standard 8 x 8 x 16 nominal concrete block covers about 0.89 square feet of wall face before waste.
Inputs
Results
Immediate estimateConcrete blocks175 blocks144 sq ft net wall area
Gross wall area144 sq ft
Openings0 sq ft
Base block count162 blocks
Mortar estimate5 bags
Shopping list
- 175 blocks 8 x 8 x 16 in concrete blocks
- 5 bags Masonry mortar — Use the product label and joint size for final ordering.
Diagram
Block wall takeoff
Wall face area minus openings is divided by nominal block coverage before waste.
- Wall length
- Wall height
- Openings
How this calculator works
Enter wall length, wall height, openings, and block size to estimate CMU block count and mortar bags.
Area model
The calculator multiplies wall length by wall height, subtracts openings, and divides by the nominal block face module.
Purchase model
The block count is rounded up after waste, then mortar bags are estimated from an editable blocks-per-bag yield.
Masonry scope
This is a material estimator. Reinforcement, grout, footings, lintels, bond beams, and structural design are intentionally outside the MVP.
Net wall area
wall length x wall height - openingsBlocks
net wall area / nominal block face area + wasteMortar
rounded block count / blocks per mortar bag, rounded upAssumptions
- Nominal face: Common 8 x 16 in nominal face module with mortar joint allowance.
- Scope: Block and mortar quantity only; grout, bond beams, reinforcement, lintels, footings, and caps are separate.
Worked examples
Wall with openings
Subtracts doors or windows from the face area.
305 blocksConcrete blocksFAQ
Is a cinder block calculator different from a CMU calculator?
For common search intent, no. This page estimates concrete masonry units using the nominal face size; local products and terminology vary.
Should I subtract windows and doors?
Yes. Enter the total square footage of openings so the block estimate is based on net wall area.
Does this include grout or rebar?
No. Grout and reinforcement depend on wall design, spacing, cells to fill, and local requirements.
Sources and review
- Concrete Masonry Unit Shapes, Sizes, Properties, and Specifications, Concrete Masonry & Hardscapes Association. Accessed 2026-07-20.
Reviewed 2026-07-20. Planning estimates only; confirm project-specific requirements.