Outdoor & gardenFree calculator
Plan a new fence by entering its length and the post spacing. You get the number of panels, posts and bags of post concrete, plus a cost estimate in your currency.
Your shopping list
How to measure
- Measure the full run of the fence along the ground.
- Use the panel width as the post spacing: 8 ft in the US and Canada, 6 ft (1.83 m) for UK panels.
- Add one extra post for every gate or corner.
The formula
Sections = fence length ÷ post spacing (round up) Posts = sections + 1
Worked example
A 100 ft fence with posts every 8 ft needs 13 sections (12.5 rounded up), so 13 panels and 14 posts.
Tips before you buy
- Check your property line and local height rules before you build.
- Call before you dig to avoid buried cables and pipes.
- Gravel boards at the bottom keep panels off wet ground so they last longer.
Frequently asked questions
How deep should fence posts go?
About a third of the post's above-ground height, and below the frost line in cold areas of Canada and the northern US.
Do corners need extra posts?
Yes. Each corner or gate adds a post, so measure each straight run separately.
How many bags of concrete per fence post?
Usually one to two 50 lb bags in the US, or one 20 kg bag of postcrete in the UK, per post.
Results are estimates for planning only. Always check quantities with your supplier before you buy.