How many retaining wall blocks do I need?

Wall face area divided by the visible face area of one block gives the base count before waste.

Should buried blocks be counted?

Yes. Base courses and caps are real material and should be added to the estimate when applicable.

When does a retaining wall need engineering?

Rules vary, but walls over about 4 feet, walls supporting surcharge, or walls near structures often need design help.

Retaining Wall Calculator · True Build Cost

Inputs

Enter your measurements

Change any field and the results update instantly. Use supplier specs when you have them.

Wall lengthftWall heightftBlock facesq ftWaste%

Tips & notes

Before you order

Assumptions that most often change the final quantity in the field—so you order with clearer eyes.

Check local rules because taller retaining walls often require engineering or permits.

Include buried base courses when ordering block.

Use clean drainage stone and pipe behind the wall to relieve water pressure.

Step the wall with grade instead of burying tall exposed courses unevenly.

Retaining Wall Calculator FAQs

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