Baluster Spacing Calculator
Calculate the number of balusters needed for railings and decks. Enter railing length, baluster spacing, and thickness for equal spacing layout.
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Spacing Results
balusters Needed17
Actual Spacing3.92 in
Frequently Asked Questions
How many balusters for 10 ft of railing?
With 4" max spacing and 1.5" balusters: (120" / 5.5") = 22 balusters. Round to 22.
What is the maximum baluster spacing?
Per IRC R312.2, a 4" sphere must not pass through any opening. This means max clear space between balusters is 4".
How do I space balusters evenly?
Use this formula: (rail length - n × thickness) / (n + 1) = spacing. Adjust n until spacing is ≤ 4".