Lumber Calculator | How Much Wood You Need + Cost

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You don’t want to start a project without enough necessary materials, such as lumber. It will also be a waste of money if you have too much. Thus, this lumber calculator will ensure you get the right amount of wood as well as calculate how much your project’s total cost will be. 

Board Feet and Linear Feet Explained

Let’s discuss the difference between board feet and linear feet. 

Board foot is a 3D measurement of the thickness, height, and width of the wood. In short, the board foot is the volume of the lumber. A board foot is equivalent to one inch thick and one square foot.

different lumber sizes

Multiplying the length in feet, width inches, and thickness in inches to calculate the board foot volume. 

A linear foot is a length measurement. It is equivalent to 12 inches. You can measure it using a ruler. 

Nominal and Actual Size

You can measure lumber in two ways. It has a nominal size that is different from its actual size. Due to some historical practices [1], the nominal size is bigger than the exact measurement. The lumber boards are not measured precisely at 2 x 4 inches.

The planing and drying procedures leave the wood with a thickness of 1 ½ inch and a width of 3 ½. These methods give a standard nominal size of 2 x 4 inches.

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Lumber Calculator Formula

If you have the number of lumber and the dimensions you need, here’s the formula used to get the total size. 

Board feet = length (ft) x width (in) x thickness (in) / 12

treated lumbers

After getting the volume of the lumber, you may now use the lumber calculator to multiply it by the number of wood pieces needed.

Lumber Project Price Calculator Formula

If you know the price of each wood, the calculator can also total the cost of your project. Take note of the lumber calculation difference between linear and board foot. Here is the formula behind the calculator:

Cost = Price per Linear Foot x Linear Feet

Cost = Price per Board Foot x Total Board Feet

You might want to check out: 2×4 Lumber Pricing 

Synthetic or Regular Wood?


Scratch-resistant, easier to install than regular hardwood, cheaper than hardwood, and can adapt well to changing weather and humidity.


It’s waterproof, but it is prone to fading.

Natural Wood

If there are damages or scratches, you can refinish it; however, keep in mind that refinishing can be more difficult and expensive than installing new materials.

Robert Johnson is a woodworker who takes joy in sharing his passion for creating to the rest of the world. His brainchild, Sawinery, allowed him to do so as well as connect with other craftsmen. He has since built an enviable workshop for himself and an equally impressive online accomplishment: an extensive resource site serving old timers and novices alike.
Robert Johnson
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