Deck Board Calculator
Estimate deck boards. Adjust board width, gap, length and a waste factor.
Quick guide
- Confirm board width (actual, not nominal) and the gap you plan to leave.
- Measure deck length and width using finished dimensions.
- Add waste for cuts and odd layouts (often 5–10%).
Deck Board Calculator
Estimate deck boards. Adjust board width, gap, length and a waste factor.
Units
Results
- Estimated boards
- 25
How to measure your deck
- Use the finished frame size (length × width).
- If the deck is L-shaped, measure each rectangle and add them.
- Include any steps or landings you plan to deck over.
Assumptions to double-check
- This estimates deck boards, not joists, beams, posts, or fasteners.
- Actual board coverage depends on board width and your gap spacing.
- Stairs, picture framing, and patterns can increase waste significantly.
Buying tips
- Confirm actual board width and recommended spacing for your material.
- Round up if you have stairs or many cuts, and keep a few spare boards.
- If matching color later matters, buy extra from the same batch when possible.
Last updated: Dec 2025
FAQ
Does this include joists or framing?
No. This calculator estimates decking boards only.
What board width should I use?
A common decking board is nominal 1×6 with an actual width around 5.5 inches.
What gap is typical?
Many decks use a small gap (e.g. 1/8 in) for drainage; follow your product guidance.
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Results are estimates for informational purposes only. Always verify measurements and product specifications.