Baluster Spacing Calculator
Plan balusters between posts or rails with clear spacing and mark locations.
Layout
Layout marks
Measured from the starting edgeProject Job Sheet
Project
Dimensions
Layout
Mark list
Space balusters evenly across a finished opening
Balusters are a classic layout problem because the installed width of the baluster and the allowable clear opening both matter. This calculator uses the clear opening between posts or boundaries, the actual baluster width, and your maximum clear gap to find an even pattern.
What to measure
Use the finished clear distance between the two surfaces that bound the baluster run. Then enter the real face width of the baluster. MeasureMarks adds balusters until the calculated clear gap is no larger than the limit you entered and gives you the center line of every baluster.
Safety note
Baluster opening rules vary by project type and jurisdiction. Use the maximum-gap field to model the requirement that applies to your project, and verify the current code or inspector requirement before construction.
- Measure after posts and rails are in their final positions.
- Use one starting edge for every center mark.
- Check both the calculated clear gap and the visual blueprint before fastening.
Is this a code-compliance checker?
No. It performs spacing math from the limit you enter; you are responsible for choosing the correct requirement.
Why use actual baluster width?
Even a small difference in width changes the remaining clear space across a full railing section.