Work out the posts, rails and pickets you need to build a fence — enter the length, post spacing and picket width to get a full materials count.
| Item | Value |
|---|
A timber fence is built from three main parts: posts set at regular spacing, horizontal rails between the posts, and vertical pickets or palings fixed to the rails. The number of each depends on your fence length, how far apart the posts sit, and the width of your pickets.
| Fence type | Post spacing | Rails |
|---|---|---|
| Paling / picket fence | 2.4 m | 2–3 |
| Colorbond | 2.4–2.5 m | 2–3 |
| Post-and-rail | 2.7–3.0 m | 2–4 |
For a 30-metre paling fence with posts every 2.4 m: the number of sections is 30 ÷ 2.4 = 12.5, rounded up to 13. Posts are always one more than the sections, so 14 posts. With two rails per section, that’s 13 × 2 = 26 rails. For 90 mm pickets with a 10 mm gap, each picket covers 100 mm, so 30 metres needs 30 ÷ 0.1 = 300 pickets.
A durable fence starts with the posts, since they carry the whole structure. Posts should be set in concrete, spaced evenly — 2.4 metres is the standard for timber paling fences because it balances strength against the number of posts needed. The corner and end posts take the most load and are sometimes set deeper or braced. Rails span between posts: two rails suit fences up to about 1.8 metres, while taller fences benefit from a third rail in the middle to stop the palings bowing. When ordering, always add a few extra posts and pickets. Timber varies in quality, some pieces will be too bowed or split to use, and having spares on hand means you won’t have to stop work for a second trip. It’s also worth checking local fencing regulations and, for boundary fences, talking to your neighbour before you start, since shared fences often involve shared costs.
How many fence posts do I need?
Divide the fence length by your post spacing (usually 2.4 m) and round up to get the number of sections, then add one — a 30 m fence at 2.4 m spacing needs 13 sections and 14 posts. The calculator does this and also counts rails and pickets.
How far apart should fence posts be?
For a standard timber paling fence, posts are usually spaced about 2.4 metres apart. Colorbond fences are similar, while post-and-rail fences can go wider at 2.7–3.0 m. Enter your spacing above to match your design.
How many pickets do I need for a fence?
Divide the fence length by the picket width plus the gap between pickets. For 90 mm pickets with a 10 mm gap, each picket covers 100 mm, so a 30 m fence needs about 300 pickets. Enter your picket width and gap for an exact count.
How many rails does a fence need?
Most fences use two or three horizontal rails per section — two for lower fences, three for taller ones (over about 1.8 m) for extra strength. The calculator multiplies your rails-per-section by the number of sections.
How many fence posts do I need?
Divide the fence length by the post spacing and round up for the number of sections, then add one. A 30 m fence at 2.4 m spacing needs 13 sections and 14 posts.
How far apart should fence posts be?
About 2.4 metres for a standard timber paling fence. Colorbond is similar; post-and-rail fences can go wider at 2.7–3.0 m.
How many pickets do I need?
Divide the fence length by the picket width plus the gap. For 90 mm pickets with a 10 mm gap, each covers 100 mm, so a 30 m fence needs about 300 pickets.
How many rails does a fence need?
Two rails per section for fences up to about 1.8 m, three for taller fences to keep the palings straight and add strength.
Should I set fence posts in concrete?
Yes — setting posts in concrete gives the fence its strength and stops them shifting or rotting at ground level. Corner and end posts especially should be well concreted.