Deck Post Quantity Calculator
Estimate preliminary deck-post positions, total posts and footing allowance from deck length, beam-row count, target spacing and end setbacks.
Default project preview
14 posts
Beam rows
2
Posts per row
6
Calculated spacing
6 ft
Supported beam length
30 ft
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Usable beam length = deck length − two end setbacks. Spaces are rounded up from target spacing; posts per row = spaces + 1.
FAQ
Deck Post Quantity Calculator questions
Can posts always be spaced at the entered distance?+
No. Structural beam spans and loads determine the maximum permitted spacing.
Why include extra posts?+
Stairs, beam splices, landings, corners or concentrated loads may need additional support.
Does the calculator size footings?+
No. Footing dimensions depend on loads, soil, frost depth and local requirements.