Concrete Block Calculator

Enter the wall length and height first. Use the openings option for doors or windows, then adjust waste, grout, and reinforcement assumptions if your project needs a fuller material list.

Primary output 189 blocks
Length of the block wall in feet.
Finished wall height in feet.
Choose the CMU thickness. The 8 in × 16 in face coverage is the same for these standard blocks.
Leave this off for a plain wall, or turn it on to subtract doors and windows before estimating materials.
Use one equivalent opening size, or run separate walls when openings differ a lot.
Width of each door or window opening in feet.
Height of each door or window opening in feet.
Extra blocks for cuts, breakage, corners, and site handling.
Advanced options
Net wall area 160 sq ft Vertical rebar 6 bars Notes —
The standard planning basis is a 3/8 in joint.
Turn this on when you need a grout quantity for filled cells.
Choose full-wall grouting or only reinforced cells at the vertical rebar spacing.
On-center spacing in inches. ACI/TMS seismic provisions commonly cap vertical reinforcement spacing at 48 in for higher seismic design categories.
Spacing in inches for ladder or truss joint reinforcement.
Preset buttons above fill the same common project values.
Blocks to order 189 blocks
Net wall area 160 sq ft
Mortar bags 6 bags
Vertical rebar 6 bars
Show calculation details
Grout fill Not included
Mason sand 0.95 tons
Gross wall area 160 sq ft
Horizontal reinforcement 120 linear ft
Notes —