UnitConv

Fence Calculator

Estimate posts, rails and pickets for a fence run

Posts needed
11
posts
Sections
10
Rails
20

Based on 2 rails per section.

Fence length24 m

Bar scaled to a 50 m (≈160 ft) reference.

Formula

Sections = ceil( length / post spacing )

Posts = sections + 1

Rails = sections × rails per section

Lengths are converted to meters first. The fence is split into sections by the post spacing, posts are one more than the sections, and rails and pickets are derived from there.

What is a Fence Calculator?

A fence calculator works out the materials for a straight fence run from its total length and the spacing between posts. Enter the total length and the post spacing, and the tool divides the run into equal sections, rounding up so no section is over-stretched. The number of posts is always one more than the number of sections, because both ends need a post. Multiply the sections by the rails (horizontal rails) per section to get the total rails, and add an optional picket width and gap to estimate the number of vertical pickets. It works for wood, vinyl, composite and metal fences in both metric (m, cm) and imperial (ft, in) units, for garden boundaries, paddocks and privacy fences.

How to Use

1. Choose metric or imperial units. 2. Enter the total fence length. 3. Enter the post spacing (2.4 m / 8 ft is common). 4. Set the number of rails per section (2 for short fences, 3 for tall). 5. Optionally enter the picket width and gap to estimate pickets. 6. Read the posts, sections, rails and pickets.

Formula & Definition

Sections = ceil( length / post spacing ) Posts = sections + 1 Rails = sections × rails per section Pickets = total length / (picket width + gap) For example, a 24 m fence with 2.4 m spacing has ceil(24 / 2.4) = 10 sections, 11 posts and, at 2 rails per section, 20 rails.

Interpreting Results

The headline figure is the number of posts to buy, since posts are the costliest part and easiest to miscount - remember it is always one more than the sections because both ends need a post. Sections are the gaps between posts; rails are the horizontal members spanning each section (2 for fences up to about 1.2 m, 3 for taller ones). The picket count is an estimate based on the width plus gap you enter; round up and add a few spares for cuts. Add corner and gate posts to the total yourself, as those depend on your layout.

Frequently Asked Questions

How many fence posts do I need? ▾

Divide the total length by the post spacing and round up to get the sections, then add one. For example, 24 m at 2.4 m spacing is 10 sections and 11 posts. This calculator does it for you.

What is the right spacing for fence posts? ▾

2.4 m (8 ft) is the most common for wood and vinyl panels; 1.8-2.4 m (6-8 ft) is typical overall. Closer spacing makes a stronger, stiffer fence but uses more posts.

How many rails per section? ▾

Two rails (top and bottom) for fences up to about 1.2 m (4 ft); three rails for taller fences to stop the pickets bowing. Heavy-duty fences may use more.

How many pickets do I need? ▾

Divide the total length by the picket width plus the gap between pickets, and round up. Enter both values and the calculator estimates the pickets for you.

Does it work for wood, vinyl and metal fences? ▾

Yes. The post, section and rail math is the same for any panel or board fence - just enter your length, spacing and rails per section.

This tool provides general estimates for planning only. It does not include corner posts, gate posts or hardware; measure carefully and confirm quantities with your supplier before purchasing.