MaterialEstimate › Outdoor Calculators › Decking

Decking Calculator

Estimate deck boards, deck square footage, and linear feet of decking based on board size and waste.

Decking Calculator
✓ Your estimate
Estimated decking needed
--
deck boards
Switch display unit only.
--
Deck sq ft
--
Sq ft incl. waste
--
Linear ft of boards
--
Deck boards
View units
Calculate first to see unit conversions.

What this estimate includes

This estimate shows deck area, decking boards, and total linear feet based on the board width, board length, and waste setting.

How it’s calculated

Deck area = length × width
Adjusted area = deck area × waste %
Linear feet = adjusted area ÷ board width
Boards = linear feet ÷ board length, rounded up

Before you order

Board spacing, picture-frame borders, stairs, diagonal layouts, and cut patterns can change the final board count. Confirm the layout before ordering.

Need related estimates? Try the lumber / stud calculator or concrete footing calculator.

Frequently Asked Questions

What board width should I use?
Many 5/4 deck boards are about 5.5 inches actual width. Use the actual installed board width for the best estimate.
Does this include board gaps?
This calculator uses board width for planning. Small gaps are typically offset by trimming and waste, but exact layouts may vary.
Should I add waste for decking?
Yes. Ten percent is a common planning buffer for straight layouts; diagonal layouts, borders, and stairs may need more.
Disclaimer: This calculator provides estimates only. Actual quantities depend on product coverage, jobsite conditions, waste, and supplier details. Verify all quantities before ordering. See all outdoor material calculators.