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Materials & Projects

Deck Board Calculator

Enter the deck surface dimensions and board details to estimate the number of deck boards needed.

Last updated: May 2026

Unit system Switch between U.S. customary and metric units. Your choice is remembered on other calculators.

Deck and board measurements

Length and width describe the deck surface. Board width and gap describe the decking layout.

ft
ft
in
Use actual board width. A nominal 5/4x6 deck board is often about 5.5 in wide.
in
Check the decking manufacturer. Common finished gaps are often around 1/8–1/4 in depending on product and conditions.
ft
Advanced settings
%

Buying and sizing notes

How to use this estimate

What this includes

  • The required inputs shown on this page
  • common planning assumptions
  • optional advanced adjustments where provided

What it does not include

  • site-specific professional design
  • local code approval
  • manufacturer-specific requirements
  • installation quality

Common mistakes

  • Leaving a required input at the default when your situation is different
  • ignoring product labels or ratings
  • treating the estimate as an exact final answer

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