Deck Board Material Calculator

Calculate how many deck boards, hidden fasteners, and screws you need for a deck, given the deck’s size and preferred board length. Estimate the cost of decking, hidden fasteners, and screws by entering a price per board.

Optionally enter the price per deck board

Material Estimate:

Deck Boards
Hidden Fasteners

Estimated Material Cost:

Deck Boards
Hidden Fasteners
*Estimates only - costs vary by location/vendor, selected material, and quantities.
Learn how we calculated this below

On this page:

How to Estimate Decking

Newly installed deck with composite decking, hidden fasteners, and screws

Decks are a great way to add usable outdoor space to your home. There are many flooring surface options, including composite decking, cedar lumber, pressure-treated lumber, and exotic hardwoods.

Consider budget, durability, and maintenance when choosing the flooring material for your project. Composite decking is virtually maintenance-free, but it carries a higher cost than pressure-treated or cedar lumber.

It’s also important to consider the flooring fasteners you want to use, such as a hidden fastener or face-screwing the boards so you can estimate the correct materials to order.

Estimate Using a Calculator

Before you start your new project, you’ll need to estimate how much deck flooring you need for the project. There are a few different ways to estimate decking, but the easiest is to use the calculator above.

To use our calculator, you’ll need to know your deck’s size and the boards you want to use. Most boards are available in 3 12” or 5 12” widths and 8′, 10′, 12′, or 16′ lengths. You’ll also need to know the joist spacing you are planning to use, most commonly 12″, 16″, 20″, or 24″.

If you want a deck flooring price estimate, you can also include the price per board. If you need to estimate your railing balusters use our baluster calculator.

Steps to Calculate How Many Deck Boards You Need

You can calculate how many boards you need in three easy steps.

Stack of composite deck boards

Step One: Find Deck Area

Estimating deck flooring materials begins with finding the square footage of your project. You can multiply the deck’s length in feet times the width in feet to find the square footage.

Check out our square footage calculator for tips on calculating the square footage of oddly shaped areas.

Step Two: Find Board Area

Once you have the deck’s square footage, you need to find the square footage of the board you’ve selected in feet. To find this, multiply the width of the floor-board in feet times the length in feet.

Try our feet and inches calculator to convert the board width in inches to feet, or just divide the inches by 12 to get the dimensions in feet.

Step Three: Calculate Boards

To find the number of boards you need, divide the total deck square footage by the board square footage. Use the following formula.

deck boards needed = total sq ft / board sq ft

Deck Estimation Tips

Now that you’re a pro at estimating deck boards, consider the following tips as you continue to plan your project.

Order Extra Material

In addition to measuring the deck area, you should also measure how much lumber you’ll need for stairs. It’s a good idea to order 10% additional lumber to account for waste and off-cuts.

Order Extra Fasteners

Also, don’t forget to order enough fasteners for your project, such as hidden fasteners or stainless/coated screws. You will want to order the correct fasteners for the type of decking you’re ordering. Some products, such as composite boards, may require a specific type of hidden fastener or screw.

Different Decking Materials are Sold Differently

While most composite or softwood decking is sold by the board, some hardwood or exotic options are sold by the board foot. If that’s the case, use a board footage calculator to estimate how much lumber you’ll need for the project.

Estimate the Total Cost

Before you start your project, you should refer to our deck cost calculator to get an idea of how much it costs to build a deck and what options are available.

Get Professional Estimates in Addition to Research

We have several great resources to help with your deck project. Get a free estimate from a local contractor if you’re interested in having someone else quote the project. Estimate how much concrete you need for your posts with our concrete hole calculator.

Share deck board material calculator