Free Retaining Wall Calculator
Calculate how many retaining wall blocks you need based on wall dimensions and block size.
ft
ft
in
in
Total Blocks
198
Blocks per Row20
Number of Rows9
Total Blocks vs Wall Length
Retaining Wall Block Calculation
Blocks per Row = Wall Length (in) / Block Length
Rows = Wall Height (in) / Block Height
Total = Blocks per Row × Rows × 1.1 (waste)
Example Calculation
20 ft long, 3 ft high wall with 12×4 in blocks.
- 01Blocks per row = 240/12 = 20
- 02Rows = 36/4 = 9
- 03Base total = 20 × 9 = 180
- 04With 10% waste = 198 blocks
Frequently Asked Questions
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