Work out the posts, rails and pickets you need for a wood, picket, privacy, chain link or vinyl fence — in metric or imperial units, with an estimated cost.
Enter your fence length and post spacing below (metres or feet — use the toggle) and the calculator instantly gives you the number of posts, rails and pickets needed. Posts = sections + 1; pickets = length ÷ (picket width + gap).
| 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.
This calculator's post/rail/picket maths applies to any fence built from posts and horizontal rails, but the numbers you plug in change with the fence style. Use the "Fence type" dropdown above to jump to sensible defaults, then adjust for your own measurements.
| Fence type | Typical post spacing | Notes |
|---|---|---|
| Wood paling / picket fence | 2.4 m (8 ft) | Pickets butted close with a small gap; use the picket count |
| Privacy fence | 2.4 m (8 ft) | Same as paling, but boards are tight together (gap ≈ 0) |
| Chain link fence | 3.0 m (10 ft) | No pickets — mesh is bought by the roll/length instead |
| Vinyl / PVC fence | 2.4 m (8 ft) | Sold in pre-made panels; use panel width as "post spacing" |
| Post-and-rail | 2.7–3.0 m (9–10 ft) | No pickets — open rail-only style |
Fence building conventions differ by country as much as the units do. Australian and UK tradespeople measure fence runs in metres and post spacing at 2.4 m; US and Canadian fence builders work in feet, with 8-foot spacing being the standard equivalent. Picket widths follow the same split — Australian palings are commonly 90mm or 100mm wide, while US pickets are usually sold in nominal inch widths like 3.5" or 5.5" (dressed size of a 1×4 or 1×6 board). Use the Metric/Imperial toggle above to switch between the two without doing the conversion by hand.
How many fence posts do I need?
Divide the fence length by your post spacing (2.4 m / 8 ft is standard) 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, in metric or imperial.
How far apart should fence posts be?
For a standard timber paling or privacy fence, posts are usually spaced about 2.4 metres (8 feet) apart. Colorbond and vinyl panel fences are similar, while post-and-rail and chain link fences can go wider at 2.7–3.0 m (9–10 ft). 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 (3.5") pickets with a 10 mm (0.4") 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 / 6 ft) for extra strength. The calculator multiplies your rails-per-section by the number of sections.
Does this work as a chain link fence calculator?
Yes — select "Chain link fence" from the fence type dropdown, which switches off the picket count (chain link mesh is bought by the roll length, not counted individually) and leaves you with the post and rail/tension-wire counts based on your spacing.
Can I use this as a vinyl or PVC fence calculator?
Yes — vinyl and PVC fences are typically sold as pre-made panels, so set "Post spacing" to your panel width (commonly 6 or 8 ft / 1.8–2.4 m) to get an accurate post count for your run.
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, in both Australian and US fence-building practice.