Deck Board Calculator — Boards Needed
Enter the deck area and board size to get the number of deck boards required.
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How it works
linear feet = (area ÷ (board_width_in ÷ 12)) × (1 + waste%); boards = ceil(linear feet ÷ board_length)
Deck boards by deck size (5½-in boards, 16 ft long, 10% waste)
| Deck size | Deck area | Linear feet | 16-ft boards |
|---|---|---|---|
| 10 × 10 ft | 100 sq ft | 240 ft | 15 |
| 12 × 12 ft | 144 sq ft | 346 ft | 22 |
| 12 × 16 ft | 192 sq ft | 461 ft | 29 |
| 16 × 16 ft | 256 sq ft | 614 ft | 39 |
| 16 × 20 ft | 320 sq ft | 768 ft | 48 |
For 5½-inch-wide boards (standard 2×6 or composite) at 16 ft long with 10% waste. Narrower 5¼-inch boards need a few more. Diagonal or picture-frame layouts add waste.
Frequently asked questions
How many deck boards do I need for a 12×16 deck?
A 12×16 ft deck is 192 sq ft. With 5½-inch-wide boards that is about 461 linear feet — roughly 29 boards at 16 ft long, including 10% waste. A 12×12 deck needs about 22 boards.
How many deck screws do I need?
Figure about 350 screws per 100 sq ft of decking — two screws at each joist crossing, with joists 16 inches on center. A 192 sq ft deck takes roughly 700 screws. For grooved boards with hidden fasteners, buy by the deck-area coverage on the box.
How many screws go in each deck board?
A 16-ft board laid across joists 16 inches on center crosses about 12–13 joists and gets two screws at each — roughly 24 screws per board. That works out to the ~350 screws per 100 sq ft above.