FREE · CALCULATORS & CONVERTERS
Deck Board Calculator.
Estimate deck boards and joists from the deck size, board width, gap, stock length and joist spacing.
Boards are assumed to run the full length in one piece of stock. The count rounds up after waste and does not stagger joints. Local arithmetic only. This is a quantity or geometry estimate, not a code check and not a substitute for a licensed professional.
- Area
- 10.8 m²
- Boards
- 21
- Joists
- 8
- Joist length
- 28.8 m
Board count uses the deck area divided by the board width plus the gap, then by the stock length, with waste, and rounds up. Joists are floor(width / spacing) + 1. Boards are assumed to run along the length.
How to use Deck Board Calculator
Enter the deck so the length follows the boards. The gap is added to the board width. Joists cross the width.
How it works
Estimate deck boards and joists from the deck size, board width, gap, stock length and joist spacing. Boards are assumed to run the full length in one piece of stock. The count rounds up after waste and does not stagger joints. Local arithmetic only. This is a quantity or geometry estimate, not a code check and not a substitute for a licensed professional.
Example
A 3.6 m × 3 m deck with 140 mm boards and a 10 mm gap.
Questions about Deck Board Calculator
Is Deck Board Calculator free, and do I need an account?
Yes. This tool is free to use in your browser without an account. Processing takes place on your device.
What are the limits and what should I check?
Boards are assumed to run the full length in one piece of stock. The count rounds up after waste and does not stagger joints. Local arithmetic only. This is a quantity or geometry estimate, not a code check and not a substitute for a licensed professional. Review the result before using it in your work.
Is my input sent to a server?
Your input is processed in your browser and is not uploaded by this tool. Files and pasted text are cleared when the page is refreshed. Normal website requests are still required to load the page and its libraries. Read the privacy explanation.