FREE DIY ESTIMATOR

Deck Calculator

Estimate decking board count, row count, waste allowance, and primary board cost for a rectangular deck.

Open the deck calculator →

How to estimate deck boards

Enter the deck length and width along with the actual board width and board length. The calculator estimates how many boards are needed and adds your selected waste allowance.

Planning tips

  1. Measure the finished deck footprint.
  2. Confirm the actual installed width of your decking boards.
  3. Choose board lengths that suit your framing and layout.
  4. Include extra material for cuts, defects, and future repairs.
  5. Check manufacturer spacing and fastening requirements.

What is not included

Framing lumber, footings, railings, stairs, fascia, fasteners, joist tape, permits, and structural design are separate from the basic decking-board estimate.

Plan beyond the boards

Use the Project Planner to add framing, fasteners, trim, and other supplies to your project list.