Retaining Wall Calculator
Combines face area block estimate with gravel volumes for base and back drain zone.
Reviewed by MaterialNeeded Editorial Team, Editorial review for field workflows and ordering assumptions.
Step 1: Units
Step 2
Enter project measurements
Use decimals if needed (e.g. 3.5).
Step 3
How to use this calculator
Enter wall length, average exposed height, backfill width behind face, and base thickness.
What the math is doing
Blocks from face sf × 1.33; base strip 4 ft wide; drain volume = length × height × backfill width.
Frequently asked questions
Geogrid layers?
Not included in block count.
Engineering?
Heights usually require design.
Drain pipe?
Add pipe SKU separately.
Cap units?
Linear feet of caps.