CONSTRUCTION CALCULATORS / PROJECT ESTIMATOR
Retaining Wall Calculator
Estimate retaining wall blocks from exposed wall dimensions, block face area and waste. Review buried courses, caps, drainage and engineering exclusions.
Inputs to confirm: wall length, height, block face dimensions and waste.
Calculate your materials
Adjust the inputs to match your project. Results update when you select Calculate.
Preliminary planning only. Confirm actual material specifications, safety and local code requirements.
Count the exposed face before planning the whole wall
Enter wall length and exposed height in feet, then the exposed face coverage of one block in square feet. Measure each wall segment separately when height changes. Use the manufacturer’s face coverage; the block’s depth is not part of this area calculation.
Block-count formula
Blocks = length × exposed height ÷ block face area × (1 + waste ÷ 100), rounded up. At the defaults, 24 × 3 = 72 ft². With 1 ft² per block and 5% allowance, 72 × 1.05 = 75.6, or 76 blocks. This is area-based rounding, not an optimization of complete courses.
Materials outside this result
The tool does not add buried courses, caps, corner units, drainage aggregate, drain pipe, geogrid or a leveling pad. Build a separate takeoff from the selected wall system’s layout and installation details. Curves and stepped foundations can change quantities even when exposed face area stays the same.
Retaining wall questions
Does the calculator determine a safe wall height?
No. Soil, retained loads, water, slopes and wall geometry affect design. Obtain the required project-specific design and permits before construction.
Are caps included?
No. Count cap units separately using the cap’s usable length and the wall’s top profile.
Why can a supplier’s block count be higher?
A supplier may include buried blocks, full-course rounding, corners and layout cuts. Compare the scope of each takeoff rather than treating the exposed-face result as the entire materials list.
Complete the materials takeoff
Use Gravel for a separately specified aggregate volume and French Drain for trench gravel. For masonry units with specified filled cores, use Concrete Block Fill.
Calculation and guidance updated October 28, 2026. Report a suspected error through Contact, including your inputs and expected result.
RESULTS