Deck Railing Calculator
Balusters = floor(length ÷ spacing) + 1 for one rail line.
Step 1: Units
Step 2
Enter project measurements
Use decimals if needed (e.g. 3.5).
How to use this calculator
Open edge length and on-center baluster spacing.
What the math is doing
Baluster count per rail line.
Frequently asked questions
Four-inch sphere rule?
Verify spacing meets code.
Top and bottom rails?
Linear feet = 2 × length per level.
Posts at corners?
Counted separately.
Stairs?
Add stair rail length.