Deck Materials Calculator
Calculate whole deck boards, rows, linear decking, joists, rim boards, fasteners, waste, and optional stair decking in imperial or metric units.
Deck dimensions
Decking boards
Optional stairs
Results
- Deck area
- 192 ft²
- Decking rows
- 26
- Pieces per row
- 1
- Decking linear length
- 416 ft
- Stock deck boards
- 29
- Joists
- 13
- Each joist length
- 12 ft
- Total joist length
- 156 ft
- Rim board length
- 56 ft
- Deck fasteners
- 676
Planning estimate. Board layout, blocking, beams, posts, railings, local spans, and code requirements must be confirmed for the project.
This tool is still being fine-tuned, so you may run into the odd error. Spotted one? Let us know so we can fix it.
What is Deck Materials Calculator?
Calculate deck materials online in imperial or metric units. Estimate deck boards, linear length, joists, rim boards, fasteners, waste, and stair treads.
How to estimate deck materials
Estimate decking boards, rows, joists, rim boards, fasteners, waste, and optional stair decking from project dimensions.
Board layout
Board direction determines both row count and framing direction. The calculator uses actual board face width plus the selected gap, then respects the purchased stock length so every row can be assembled from whole pieces.
Framing estimate
Joists are counted on center across the direction in which boards run. Total joist length and the perimeter rim-board length are listed separately for easier purchasing.
How to use it
- Choose imperial or metric units and enter deck dimensions.
- Enter board width, gap, stock length, direction, and joist spacing.
- Add waste and optional stair measurements.
- Review full boards, framing lengths, and fastener estimates.
Calculated locally
All project dimensions and material estimates remain in your browser and are never uploaded.
Frequently Asked Questions
Does the board count include waste?
Yes. The selected waste percentage applies to deck and stair decking. The result also enforces a minimum number of whole pieces for each row.
Are beams, posts, and railings included?
No. Their sizing and quantity depend on height, spans, loads, footing conditions, layout, and local code, so they need a project-specific design.
Why is joist spacing measured on center?
On-center spacing is the standard distance from the centerline of one joist to the centerline of the next.