Fence Calculator
This fence calculator works out how much material you need: posts, sections, pickets, panels or rolls of wire, rails, braces and concrete. Gates, post spacing and a closed boundary around a whole lot are taken into account.
Source: Wikipedia – Fence. Updated: .
How it is calculated
A fence consists of posts at a fixed spacing with a filling between them – pickets, ready-made panels or wire mesh. The calculator counts from the length how many sections, posts and filling parts you need.
How it is calculated
- Sections: fence length without gates divided by the post spacing, rounded up. For 80 ft with a 4 ft gate and 8 ft spacing, 76 ÷ 8 = 9.5, so 10 sections.
- Posts: an open fence needs one more post than it has sections, a closed boundary as many posts as sections. Each gate adds one post, because two gate posts stand instead of one shared post.
- Pickets: fence length divided by picket width plus gap. With 3.5 in pickets and a 0.5 in gap, one foot of fence takes 3 pickets.
- Rails: horizontal rails per section, given here in running length.
- Concrete: amount per post hole times the number of posts.
Post length and footing
As a rule of thumb a third of the post is in the ground – a 4 ft fence needs posts of about 6 ft. Gate, end and corner posts carry more load and are secured with braces. Concrete and post sleeves last, and in regions with frost the footing should reach below the frost line.
More calculators: the concrete calculator for footings, the raised bed soil calculator for beds, and the length converter to switch between meters and feet.
Frequently asked questions
How many posts do I need for 20 meters of fence?
At 2.5 m spacing that is 8 sections and so 9 posts, or 8 for a closed boundary. Each gate adds one more post.
How far apart should fence posts be?
Usually 6 to 8 feet; with ready-made panels their width sets the spacing. 8 ft is common for picket fences, closer for tall ones.
How many pickets do I need?
Fence length divided by picket width plus gap, rounded up. 10 m of fence with 9 cm boards and a 3 cm gap takes 84 pickets.
How long must the posts be?
About 1.5 times the visible fence height, because a third is in the ground. A 4 ft fence needs roughly 6 ft posts.
How much concrete do I need per post?
For a hole of 10 × 10 × 16 in about 1 cubic foot – roughly two 50 lb bags of ready-mix. Tall fences or loose soil need bigger footings.
Sources and legal basis
As of: · Editorial policy
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