Almost every short delivery on a fence job comes from the same place: somebody counted the panels and forgot that panels do not come in round numbers of feet, or counted a post for every panel and ended up one short at the end of the run. Neither mistake is hard to avoid. Both cost a return trip.
Here is the arithmetic we use in our own package configurator, so you can do it on the back of a takeoff sheet and get the same answer the website would give you.
The short answer
- Fence length = total run minus the width of every gate.
- Panels = fence length divided by the panel width, rounded up. Our US welded wire panels are 8 feet 2¾ inches wide (2,508 mm), so divide by 8.23.
- Posts = panels plus one, for a single open run. A closed loop back to its starting point needs no extra post.
- Brackets = posts times the number of brackets per post, which depends on fence height: 2 at 4 feet, 3 at 6 feet, 4 at 8 feet.
- Caps = one per post, and post length is longer than the fence height because part of it goes in the ground.
Step 1: Measure the run, not the yard
What you need is the total length of fence line, measured along the ground the fence will actually stand on. Walk it with a wheel or a tape rather than pulling dimensions off a plat, because plans do not know about the tree, the retaining wall or the drop at the back corner.
Write down how many sides the run has and how many corners. That matters for the post count later: a corner post is a post, but corners do not add to the total the way an extra open end does.
Step 2: Subtract the gates
A gate occupies fence line but is not fence. Subtract each gate's full width from the total run before you divide anything, or you will buy a panel you cannot install.
Standard widths in our US range are 4 and 5 feet for single gates and 10, 13 and 16 feet for double gates. A 100 foot run with one 10 foot double gate is 90 feet of fence, not 100.
Step 3: Divide by the panel width, then round up
Our US welded wire panels are 8 feet 2¾ inches wide, or 2,508 mm. Divide the fence length by 8.23 and round up, always up. The last panel gets cut down to fit, or the layout gets a deliberately short bay at a corner where nobody looks.
This is where round numbers cause trouble. A hundred feet of fence is not twelve panels and it is not twelve and a half panels you can order. It is 12.2 panels, which means 13 panels on the truck.
Step 4: Add the posts
Posts equal panels plus one for each open run. A single straight line of 13 panels needs 14 posts, because a fence has a post at both ends. Two separate stretches of fence with a driveway between them are two open runs, so that is panels plus two.
A run that closes on itself, all the way around a yard back to where it started, needs exactly as many posts as panels. There is no extra end post, because there is no end.
Corners do not change the count, only the type. Every corner is one of the posts you already counted, but it carries brackets on two faces, so order it as a corner post rather than a line post.
Step 5: Count what holds it together
Panels and posts are the easy part of the order. What gets forgotten is everything that connects them, and it is never a small number.
- Brackets, per post, by fence height: 2 at 4 feet, 3 at 6 feet, 4 at 8 feet. Fourteen posts on a 6 foot fence is 42 brackets, and 42 is exactly the kind of number nobody estimates correctly by feel.
- Post caps, one per post. Cheap, and an open post top collects water.
- Post length, which is not fence height. A 4 foot fence takes a post around 6 feet 1 inch long, a 6 foot fence around 9 feet 2 inches and an 8 foot fence around 10 feet 6 inches, because the difference goes in the ground.
- Setting material, if you are setting in concrete rather than driving posts. Work it out per hole and multiply by the post count, not by the panel count.
- Gate hardware, per gate leaf rather than per gate. A double gate needs two hinge sets, a drop rod and a way to hold it shut.
A worked example: 100 feet with one double gate
A single straight run, 100 feet total, 6 feet high, with one 10 foot double gate. Working through the five steps:
- Total run 100 feet, minus a 10 foot gate, leaves 90 feet of fence.
- 90 divided by 8.23 is 10.9, so 11 panels.
- One open run, so 11 panels plus 1 equals 12 posts.
- At 6 feet high that is 3 brackets per post, so 36 brackets.
- 12 post caps, 12 postholes worth of setting material, and one 10 foot double gate with hardware for two leaves.
Now change one thing. Take the gate out and the same 100 feet becomes 13 panels and 14 posts, because 100 divided by 8.23 rounds up to 13. One gate moved the panel count by two and the bracket count by six. That is the whole reason to subtract the gates before dividing rather than after.
Or let the configurator count it
The wire fence and security fence package configurators on our US site run exactly this arithmetic. Enter the run length in feet, pick the height, the wire gauge, the post and bracket type, how many sides and corners you have and which gates you need. It returns the complete bill of materials, panels, posts, brackets, caps, setting material and gates, priced line by line against real products, and adds the whole thing to your cart in one action.
Use it as a check on your own takeoff even when you plan to order the parts separately. If your count and the configurator's count disagree, one of you forgot the gate.
Frequently asked questions
How many posts do I need for 100 feet of fence?
Fourteen, for a single straight run with no gates, using 8 foot 2¾ inch panels. 100 divided by 8.23 is 12.2, rounded up to 13 panels, plus one end post equals 14. Add a 10 foot gate to the same run and it drops to 11 panels and 12 posts.
Do I need a post between every panel?
Yes. Every panel is bolted to a post at each end, so consecutive panels share a post. That is why the count is panels plus one and not panels times two.
What if the run does not divide evenly into panels?
It almost never does. Round up and cut the last panel to width on site, or plan a short bay at a corner where the difference is least visible. Do not round down and hope, and do not stretch the bay spacing to make the numbers work, because a rigid panel does not stretch.
How deep should the posts go?
Deep enough for your local code and below your local frost depth, which varies by state and by county. Check the requirement for your jurisdiction before you dig. Our posts are supplied long enough for the fence height plus a set depth, which is why a 6 foot fence ships with a post over 9 feet long.
Do corner posts count as extra posts?
No. A corner is one of the posts already in your count. What changes is the part: it carries brackets on two faces, so order corner posts as corner posts and line posts as line posts.
Get the count checked
Send us your run length, height and gate positions and we will price the whole package, including the brackets nobody counts. Build it yourself in the fence package configurator, or call 214 878 1900 and we will do the arithmetic with you.