How this calculator works
Subtract the width of the gates from the total length, and divide what remains by the width of a panel, rounding up. A fence needs one more post than it has panels, and each gate adds one more post. Posts are buried about a third of the fence height, and at least 600 mm, so a 1.8 m fence takes a 2.4 m post.
Worked example: 10 m of 1.8 m fence with one 0.9 m gate: the run is 9.1 m, and 9.1 ÷ 1.83 = 4.97, so 5 panels. That needs 5 + 1 + 1 = 7 posts of 2.4 m, and 5 gravel boards.
Tips before you buy
- In England, a fence over 2 m high, or over 1 m next to a highway, usually needs planning permission, and other parts of the UK have their own rules. Check with your council, and check who owns the boundary.
- Fit gravel boards under the panels so that the timber does not touch the soil, which makes the panels last much longer.
- Set the posts in concrete (or use post spikes or concrete posts), at the spacing the panels need, and check them for plumb in both directions.
- Use pressure-treated posts rated for ground contact, and treat the cut ends of panels and posts.
- Start at the end that is most visible, or the end with the gate, so that any cut panel ends up in a less visible place.
Tools & materials for this project
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Frequently asked questions
How many fence panels do I need for 10 metres?
5 panels of 1.83 m for 9.1 m of fence, if one 0.9 m gate takes up the rest. Without a gate, 10 m needs 6 panels, with one cut down.
How many fence posts do I need?
One more than the number of panels, plus one for each gate. Five panels and a gate need seven posts.
How long should fence posts be?
The fence height plus 600 mm or a third of the height in the ground, whichever is greater. So a 1.8 m fence uses 2.4 m posts.
What is the standard size of a fence panel?
1.83 m (6 ft) wide, and 0.9, 1.2, 1.5 or 1.8 m high. Other widths are sold, so check before you order posts.
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Related calculators & guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.