Fence Calculator

Written byOleh Soloninupdated 25 September 2026

Fence length, m

Fence layout

A straight run has one more post than bays; a fence closed around a plot has as many posts as bays.

Post spacing, m

Fence height, m

Rows of rails

Effective sheet width, m

Post embedment, m

Depends on the soil and the frost line; 0.9 m is an example, not a rule.

Hole diameter, m

The bored diameter: the concrete per post follows from it.

Result

Posts25
Bays24
Post length, m2.9
Rails, m120
Sheets55
Concrete for posts, m³1.1
How it was calculated
60 m ÷ 2.5 m = 24 spans, one more post than spans — 25 post length: 2 m above ground + 0.9 m embedded = 2.9 m hole: π × (0.25 ÷ 2)² × 0.9 = 0.044 m³ per post, 1.1 m³ in total

On a straight run there is one more post than bays

Posts, bays, rails and sheets for a fence of any length, plus concrete for setting the posts.

A 60-metre fence at 2.5 m post spacing is 24 bays and 25 posts: on a straight run there is one more post than bays. A fence that closes around a plot ends on its first post, so it has as many posts as bays — pick the layout in the calculator. Two rows of rails take 120 metres, and sheets with a usable width of 1.1 m come to 55.

Concrete is counted from the hole rather than from an average: at a 0.25 m bore and 0.9 m embedment each post takes 0.044 m³, so 25 posts take 1.1 m³. Widen the bore to 0.3 m on a 100-metre run and the 41 posts need 2.61 m³.

How to use

Enter the length of the fence, the post spacing and the layout — a straight run or a closed loop; they give the bays and the number of posts.
Set the height above ground and the embedment: together they are the length of post you have to buy.
Add the hole diameter, the number of rail rows and the usable sheet width; read the materials and the concrete.

Posts, rails and concrete

Every row is a separate run of this calculator with two rows of rails and sheets 1.1 m wide.

Every value was produced by the calculator on this page.
Length	Spacing	Height	Embedment	Hole	Bays	Posts	Post length	Rails	Sheets	Concrete
60 m	2.5 m	2 m	0.9 m	0.25 m	24	25	2.9 m	120 m	55	1.1 m³
60 m	3 m	2 m	0.9 m	0.25 m	20	21	2.9 m	120 m	55	0.93 m³
40 m	2.5 m	2.5 m	1.2 m	0.25 m	16	17	3.7 m	80 m	37	1 m³
100 m	2.5 m	2 m	0.9 m	0.3 m	40	41	2.9 m	200 m	91	2.61 m³

Spacing and wind

Spacing decides two things at once: how many posts there are and how much each one carries. Going from 2.5 to 3 metres on the same run saves four posts and 0.17 m³ of concrete, but every remaining post takes more wind — and a solid profiled fence works like a sail.

Embedment is an input on purpose: there is no code figure "for a fence". It depends on the soil, the frost line and the height of the panel. The 0.9 m in the examples is an example, not a requirement.

What is counted and what is not

Posts, bays, post length, metres of rail, sheets and concrete are counted. Sheets go by usable width — for profiled sheeting that is less than the overall width by one wave of overlap, and the catalogue states it.

A gate and a driveway are not counted: their openings take sheets away and add posts of their own, heavier ones for a gate. Cutting to height is not counted either.

What this calculator shows

Posts and bays at your chosen spacing
Recommended post length including the buried section
Rail metres, sheet count and concrete volume

What to keep in mind

The 2.5 m spacing is a default example; the spacing for your panels and wind load comes from the design.
Concrete per post is the volume of a cylindrical hole: π × (diameter ÷ 2)² × embedment. The post itself is not subtracted, so the figure is slightly more than the hole will take.

FAQs

How many posts for a 60-metre fence?

At 2.5 m spacing on a straight run, 25: 24 bays plus one post. If the same 60 m closes around a plot, the estimate is 24 — as many posts as bays — though corners can add more, so count the bays side by side. At 3 m spacing 21 posts are enough, but each carries more load.

How long should the posts be?

Height above ground plus embedment: 2 m and 0.9 m make 2.9 m. A 2.5 m fence with 1.2 m in the ground needs 3.7 m posts.

How much concrete per post?

The volume of the hole: 0.25 m across and 0.9 m deep is 0.044 m³, so 25 posts take 1.1 m³. A 0.3 m bore raises it by about half.

How deep should a fence post go?

There is no code figure: it depends on the soil, the frost line and the height of the fence. That is why embedment is an input; 0.9 m in the examples is just an example.

How many sheets of profiled sheeting?

Fence length divided by the usable width: 60 m at 1.1 m is 55 sheets. Usable width is less than overall width because the sheets overlap.

How many metres of rail?

Length times the number of rows: 60 m with two rows is 120 m. Tall fences take three rows and the metres rise in proportion.

Worked example

A 60-metre fence

Input: 60 m, 2.5 m spacing, 2 m high, 0.9 m embedment, 0.25 m holes

Output: 25 posts, 24 bays, 1.1 m³ of concrete

Note: Posts are 2.9 m long, rails come to 120 m and sheets 1.1 m wide to 55.

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Result

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