Deck calculator

Enter your deck's size and board dimensions to get total area, decking boards needed, and estimated material cost.

Deck length
ft
Deck width
ft
Board width
in
Gap between boards
in
Board length
Price per board
$
Result
Deck area192.00sq ft
Boards needed29
Est. cost$812

Estimate only — includes 10% waste; excludes framing, footings, and fasteners.

How this deck calculator works

We divide deck area by the effective coverage of one board (its face width plus the gap) to find total linear feet of decking, add 10% waste, then divide by your board length to get a board count. Cost multiplies boards by your price per board.

Frequently asked questions

It depends on your deck's area and the width of your chosen board. Enter your dimensions above and we'll calculate the count, including a waste allowance for cuts.

No — this covers decking boards only. Framing lumber, footings, and hardware should be estimated separately based on your joist spacing and framing plan.