Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Deck boards needed
28
Decking material cost
$616
Linear feet of decking
441
Deck area (sq ft)
192
Joists at 16 in on center
13
Deck screws (approx)
970
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter deck length (ft).
- 2Enter deck width (ft).
- 3Enter board width (in).
- 4Enter gap between boards (in).
- 5Enter board length sold (ft).
- 6Enter price per board ($).
- 7Enter waste factor (%).
- 8Read your deck boards needed on the right — it updates as you type.
- 9Hit Share to keep the scenario or send it to someone.
About this calculator
Deck framing waste is driven by board length versus deck width. Ordering boards that span the deck in one run cuts both waste and butt joints.
Worked example
Using the values the calculator loads with:
Inputs
- Deck length: 16 ft
- Deck width: 12 ft
- Board width: 5.5 in
- Gap between boards: 0.25 in
- Board length sold: 16 ft
- Price per board: 22 $
- Waste factor: 10 %
Results
- Deck boards needed: 28
- Decking material cost: $616
- Linear feet of decking: 441
- Deck area (sq ft): 192
- Joists at 16 in on center: 13
- Deck screws (approx): 970
What each field means
Inputs
- Deck length (ft)
- The deck length used in the calculation, measured in ft. Starts at 16 ft so you have a working example on load.
- Deck width (ft)
- The deck width used in the calculation, measured in ft. Starts at 12 ft so you have a working example on load.
- Board width (in)
- The board width used in the calculation, measured in in. Starts at 5.5 in so you have a working example on load.
- Gap between boards (in)
- The gap between boards used in the calculation, measured in in. Starts at 0.25 in so you have a working example on load. Accepted range: 0–1 in.
- Board length sold (ft)
- The board length sold used in the calculation, measured in ft. Starts at 16 ft so you have a working example on load.
- Price per board ($)
- The price per board used in the calculation, measured in $. Starts at 22 $ so you have a working example on load.
- Waste factor (%)
- The waste factor used in the calculation, measured in %. Starts at 10 % so you have a working example on load. Accepted range: 0–30 %.
Results
- Deck boards needed
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Decking material cost
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Linear feet of decking
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Deck area (sq ft)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Joists at 16 in on center
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Deck screws (approx)
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the deck board & material calculator work?
Deck framing waste is driven by board length versus deck width. Ordering boards that span the deck in one run cuts both waste and butt joints. The underlying maths is: Boards = deck area ÷ (board width + gap) × length factor, plus waste.
What do I need to enter?
7 values: deck length, deck width, board width, gap between boards, board length sold, price per board, and waste factor. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the deck boards needed result mean?
It is returned as a whole number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary.
Who is this tool for?
It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Deck Board Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/deck-board-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/deck-board-calculator" target="_blank" rel="noopener">Deck Board Calculator — RevenueLab</a> (2026).</p>
Source: [Deck Board Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/deck-board-calculator) (2026).