Fence Calculator

Plan one straight fence run

Enter overall run length, maximum distance between posts, rails per section, picket width, gap, and an extra-picket allowance. Results round each material category up to whole pieces.

Sections determine posts and rails

Dividing run length by maximum section length and rounding up gives the section count. A free-standing straight run has one more post than sections because every section has two ends and neighboring sections share a post. Rails equal sections multiplied by the selected rails per section.

Picket coverage

Picket face width plus planned gap creates one repeating interval. The run is converted to inches and divided by that interval, then rounded up. The extra percentage is applied to that whole-run estimate. Actual end gaps may need adjustment so spacing looks even between posts.

Worked example

A 40-foot straight run with 8-foot maximum sections needs five sections and six posts. With two rails per section, it needs ten rails. Using 5.5-inch pickets and 0.5-inch gaps creates a 6-inch repeat, so the run starts at 80 pickets; 5 percent extra rounds the purchase estimate to 84.

Handle gates and corners separately

A gate changes post type, hardware, rail layout, and picket count. Corners, returns, shared building connections, stepped slopes, and changes in height also break the simple straight-run model. Divide a larger project into plain runs, calculate them separately, then add explicitly planned gate and corner materials.

Spacing is not structural guidance

Post spacing, embedment, post size, rail count, fasteners, and footing details depend on fence height, wind exposure, soil, material system, manufacturer instructions, and local rules. Enter section length only after choosing it from suitable project guidance.

Limitations and boundaries

The estimate excludes concrete, gravel, caps, brackets, screws, nails, stain, demolition, terrain changes, setbacks, surveys, utilities, and permits. It does not locate property lines or underground services. Confirm actual product dimensions and safe digging requirements before work.