Fence Calculator

Estimating wood privacy fence materials

Estimating Fence Materials

Calculate fence materials, posts, rails, pickets, concrete, and hardware given the fence length.

Material Estimate:



How to Estimate Privacy Fence Materials

Fences are a great way to add privacy, security, and decor to your property. They can be constructed from a variety of materials including wood, metal, vinyl, and stone. The type of material you choose depends on its purpose and the style you prefer. Wood fences are great for adding privacy and security and are commonly preferred for their style and affordability.

When building a wood fence you’ll need to determine what lumber and hardware you need and how much of each. For most wood fences you need posts, rails, pickets, concrete, and nails or screws. You may also need gate hardware, post caps, stain or paint, lighting, or other materials depending on the style you choose. We also have a tool to estimate the amount of concrete you need for your fence posts.

Once you’ve chosen a style you can enter your total length and rail and picket specs into the wood fence calculator above to get a estimated bill of materials. The calculator will estimate how much lumber you need to construct your fence, including the number of posts, rails, pickets, concrete, and nails/screws. The average fence costs $2000-$8000 to install, see how much each style of fence costs or get a professional estimate for your project to find exactly what it will cost. Learn more about how to install a wood privacy fence.

Determine Types of Lumber For a Privacy Fence

The style of fence you choose will determine what types of lumber you need. Some will have 2 horizontal rails between the posts and others will have 3, 4, 5, or more. Some fences have no pickets, while others have pickets with no gap, and others have a space between the pickets.


Solid Board Privacy Fences

Estimate the lumber needed to build a solid wood fence

A solid wood privacy fence consists of posts with 2 or 3 rails in between and pickets that have no gaps. All of the pickets are installed on the outside of the rails. The solid wood style has a good side and a bad side, and typically the good side is shown on the public-facing side of the property.

Estimating Solid Board Fence Materials

To estimate the lumber to build a solid board fence use the following values for the form above:

  • Length: *the length of your fence
  • Rails per Section: 2 or 3
  • Picket Spacing (inches): 0
  • Picket Width (inches): 5.5

For example, estimating a 100′ length solid wood style would require an estimated 14 posts, 26 rails, and 219 pickets.


Shadowbox Fences

Estimating lumber for a shadowbox style fence

A shadowbox style fence consists of posts with 2 or 3 rails in between and pickets installed on both sides of the rails with a gap between them, but overlapping the other side. Because pickets are installed on both sides, the shadowbox style looks the same on each side, so there is no good or bad side.

Estimating Shadowbox Fence Materials

To estimate the wood needed to build a shadowbox style fence use the following values for the form above:

  • Length: *the length of your fence
  • Rails per Section: 2 or 3
  • Picket Spacing (inches): -1 for a 2.5″ gap or -2 for a 1.5″ gap
  • Picket Width (inches): 5.5

A 100′ long shadowbox style would require about 14 posts, 26 rails, and 267 pickets.


Stockade Fences

Estimating parts for stockade fence

A stockade style fence consists of posts with 2 or 3 rails and pickets similar to the solid board fence. Thinner pickets are used to achieve the stockade style. Just like a solid board fence a stockade style has a good side and a bad side.

Estimating Stockade Fence Materials

Use the following values for the form above to estimate the wood needed to build a stockade fence:

  • Length: *the length of your fence
  • Rails per Section: 2 or 3
  • Picket Spacing (inches): 0
  • Picket Width (inches): 2.5

Picket Fences

Estimating parts to build a picket fence

A picket fence consists of posts with 2rails and thin pickets. The pickets are spaced evenly, usually the gap matches the width of a picket but this can vary. The pickets are installed on the same side of the rails so there is a good and bad side.

Estimating Picket Fence Materials

Use the following values for the form above to estimate the lumber needed to build a picket fence:

  • Length: *the length of your fence
  • Rails per Section: 2 or 3
  • Picket Spacing (inches): 2.5
  • Picket Width (inches): 2.5

Slip-Board Fences

How much material is needed to build a slip-board fence.

A slip-board fence consists of posts with 2, 3, 4, or more rails and no pickets. Traditional slip-board fences have 3 rails and are constructed of rough materials. Slip-board fences can also be built using common dimensional lumber.

Estimating Slip-Board Fence Materials

Although the calculator above can estimate the number of posts and rails, you may consider using different sized boards to achieve a different style. Use the following values for the form above to estimate the wood needed to build a slip-board fence:

  • Length: *the length of your fence
  • Rails per Section: 3
  • Picket Spacing (inches): 0
  • Picket Width (inches): 0

How to Estimate How Much Material You Need

How Many Posts Are Needed to Build A Fence

The first step in figuring out how much wood is needed to build a fence is to measure the length. Given the total length you can estimate the number of posts you need. To estimate the number of posts simply divide the length of the fence in inches by 96 (8′) and round up to get the number of sections, then add 1 for the last post. For instance, if your length is 1200 inches follow the formula: 1200 / 96 = 12.5, round up to 13 and then add 1 = 14 total posts needed. Posts are commonly constructed using 4×4 dimensional lumber. Check our our foot to inch conversion utility if you need help converting feet to inches.

How Many Posts Are Needed to Build A Fence

You can find how many horizontal rails you need to build a fence by multiplying the number of sections from the previous formula by the number of rails per section. If you want 3 horizontal rails and there are 13 sections use the following formula: 13 x 3 = 39. 2×4 dimensional lumber is normally used for the horizontal rails.

How Many Pickets Are Needed to Build A Fence

Calculating the pickets for a fence is the hardest part. The first step is the find the distance between each post using the calculator above and then dividing by the width of the picket plus the space between the pickets. For instance, if you are building a solid board fence using 5.5″ pickets with no space between the pickets use the following formula: 1200 / 13 = 93″ sections. 93 / 5.5 = 17 pickets. Pickets are usually a 2.5″ or 5.5″ board that is 3/4″ thick.

Tips For Estimating Fence Lumber

We recommend ordering 10% extra lumber to account for cutoffs and waste. Also plan on ordering lumber to build a gate, including extra posts and hardware. Gate posts should be 4×4 or 6×6 dimensional lumber.


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