Retaining Wall Block Calculator
Updated Formulas shown
Count blocks by wall face area. A 30 ft wall, 3 ft tall, of 12 × 4 in blocks needs about 284 blocks plus 30 caps (one per ft of 12 in cap).
Blocks
284
- Area
- 90 ft²
- Per ft²
- 3
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Frequently asked questions
How tall can a retaining wall be without an engineer?
Many jurisdictions require engineering or a permit above 3–4 ft. Check local code.
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Estimates only. Check quantities with your supplier or contractor before ordering.