How the vinyl fence calculator works
A vinyl fence is counted in panels, not boards. Each straight stretch between corner, end and gate posts is filled with full panels from one end, and whatever is left over becomes one panel cut down to fit. Every post gets a cap and its own concrete footing.
Post centers = panel width + post width. Full panels per stretch = stretch length ÷ post centers, rounded down. Last panel = leftover length − post width.
The post-center rule comes from Freedom's vinyl installation instructions: the panel rails slide into the posts, so each post adds its own width to the spacing. A 72 in panel on 5 in posts sits on 77 in centers. Bufftech lists 96 in centers on 4x4 posts and 97 in on 5x5 posts for its 8 ft picket styles, so check the sheet for your panel. When the leftover is narrower than a post, no cut panel fits, and the calculator tells you how far short the last post lands.
The material list spaces posts at the panel width itself (72 in for 6 ft panels). That is the cautious count: it can come out a panel or post higher than the plan, which leaves you a spare.
A worked example
The calculator opens on a 150 ft fence, 6 ft high, with two corners and one 4 ft gate, built from 6 ft panels on 5x5 posts.
- The gate leaves 146 ft to fence: two full sides of 50 ft and two stretches of 23 ft beside the gate.
- A 50 ft side is 600 in. At 77 in centers that is 7 full panels (539 in), leaving 61 in. Take off 5 in for the post and the last panel is cut to fill 56 in.
- A 23 ft stretch is 276 in: 3 full panels (231 in), 45 in left, so the last panel fills 40 in.
- Panel plan: 20 full panels plus 4 cut ones, 24 panels, and 26 posts with a cap each.
- The material list, on 6 ft centers, shows 26 panels and 28 posts with 28 caps. Buy that and the extras cover a cracked panel or a miscut.
- Concrete: holes 12 in wide and 42 in deep with 6 in of gravel take about 4.9 bags of 50 lb fast-setting mix each, 138 bags in all.
Switch the panel width to 8 ft and the plan drops to 18 panels and 20 posts. Fewer posts means fewer holes and less concrete, but 8 ft panels are heavier to handle and a cut throws away more.
Why so much concrete?
The default hole depth follows Quikrete's rule of half the height above ground plus 6 in of gravel, which gives 42 in for a 6 ft fence. Bufftech's guide digs 30 in holes with a 12 in auger for 5x5 posts, and its standard posts are 102 in long, 30 in more than its 72 in panel. Weatherables pairs a 5 in post with a 1 ft hole, the width used here. At 30 in deep the same fence takes 92 bags and an 8 ft post is enough. Use your manufacturer's depth, or go deeper where the ground freezes below it. The fence post depth calculator works that out from your frost line.
6 ft or 8 ft panels?
| 6 ft panels | 8 ft panels | |
|---|---|---|
| Panels for the example | 24 | 18 |
| Posts and caps | 26 | 20 |
| Cut panels | 4 | 4 |
Six foot panels are the common molded size (Bufftech's 72 in by 72 in panel). Eight foot sections are sold as privacy kits by retailers such as A Vinyl Fence, in 4, 5 and 6 ft heights. On a short run or a line with many corners, the difference in posts shrinks, because every corner, end and gate post is needed either way.
How wide is the gate opening?
Gates need more room than their nominal width. Bufftech's table gives the inside-to-inside post spacing: 38 1/2 in for a 3 ft gate, 50 1/2 in for a 4 ft gate, 62 1/2 in for 5 ft and 73 1/2 in for 6 ft. That allows about 1 1/2 in on the hinge side and 1 in at the latch. Enter the gate in the calculator at the opening width, not the gate width.
What is next?
For the price of the job, the vinyl fence cost calculator puts ranges on panels, labor and gates. If you are weighing vinyl against wood for a solid screen, the privacy fence calculator runs the same line in boards. The fence calculator compares every fence type on one drawing.