Fence Panel Calculator
Enter your total run, the panel width and any gates — get the number of panels and posts to buy, plus a quick concrete estimate for setting them.
↺ Loaded the fence length from your last calculation. Edit any field to change it.
Counting panels and posts
Pre-built panels make the take-off simple: the panels arrive assembled, so you are really only buying panels, posts and the concrete to set them. The one thing that trips people up is posts. The rule is to picture every panel and every gate as a bay that sits between two posts — a straight run of ten bays has eleven posts, not ten. This calculator counts the bays for you (panels plus gates) and adds the final post automatically.
The last panel almost always gets cut
Runs rarely divide into a whole number of panels, so plan on trimming the final one. The calculator shows how many full panels you need plus the width of the cut panel, so you know before you buy. Wood and vinyl panels can be cut down on site; welded steel and aluminum panels often cannot, so for those you either adjust post spacing to swallow the difference or order a matching accent section.
6-foot vs. 8-foot panels
Panel width drives your whole material list. Eight-foot panels cover the same run with fewer panels and, more importantly, fewer posts and less concrete — a real saving over a long fence. Six-foot panels cost less each, handle gentle slopes and curves better because the shorter bays step more cleanly, and are easier to carry. If your yard is flat and straight, 8-foot panels usually win on total cost; on uneven or winding ground, 6-foot panels are more forgiving.
Before you order
- Add a post per corner. Every corner or change of direction needs its own post beyond the straight-run count here.
- Gate posts do heavy work. Use larger or concrete-heavy gate posts — a swinging gate loads them far more than a panel does.
- Check panel height against post length. Posts must be long enough for the panel height plus your hole depth (typically 2 feet or more in the ground).
- Buy one spare panel if the style may be discontinued — matching a damaged panel years later is often impossible.
Estimates only — confirm panel and post dimensions on the exact product you buy.
Frequently asked questions
How many fence panels do I need?
Divide the length you are filling with panels by the panel width, then round up — the last panel is almost always cut to fit. For a 100-foot run with no gates and 8-foot panels, that is 13 panels (12 full plus one cut to 4 feet). This calculator does it for your exact run and subtracts any gate openings first.
How many posts for a panel fence?
Think of every panel and every gate as a bay sitting between two posts. A straight run of B bays needs B + 1 posts. So 12 panels and 1 gate is 13 bays, which needs 14 posts. Corners and direction changes add a post each, so add one more post per corner to the number shown.
Do gates change the panel count?
Yes. A gate opening takes the place of a panel, so we subtract the total gate width from your run before counting panels, then add a post on each side of every gate. Set the number of gates and the width of each opening — a common walk gate is 3 to 4 feet, a double drive gate 10 to 12 feet.
What panel width should I use?
Wood and vinyl privacy panels are usually sold in 6-foot or 8-foot widths; ornamental steel and aluminum panels are often 6 feet. Check the product — panel width sets both how many panels and how many posts you buy, so an 8-foot panel run uses noticeably fewer posts than a 6-foot one.
Is the concrete number exact?
It is a quick estimate assuming an 8-inch-wide by 24-inch-deep hole around a 3.5-inch post. Deeper holes for tall or windy-site panels use more. For an exact bag count by hole size and post size, use our post concrete calculator.