Fencing: Posts and Panels From a Run

All versions

A fence bid starts with two counts: how many panels the run needs and how many posts hold them up. Divide the run by the panel width, round up, and add one post — a fence line always has one more post than panel.

Quick formula: Round the run up to whole panels, then add one post:

=ROUNDUP(B2/C2,0)

A 120 ft run with 8 ft panels needs 15 panels and 16 posts. The last panel gets cut down on site — you still buy a whole one.

Functions used (tap for the full reference guide):

ROUNDUP

The example

Three fence lines on one property, each with its own run length and panel width.

	A	B	C	D	E
1	Fence line	Run (ft)	Panel (ft)	Panels	Posts
2	Back line	120	8	15	16
3	Side line	45	8	6	7
4	Front line	60	6	10	11

The formula

ROUNDUP turns the fractional panel count into whole panels you can actually order:

=ROUNDUP(B2/C2,0) // run divided by panel width, always rounded up

How it works

Two short steps, one for each count:

B2/C2 divides the run by the panel width — 45 ft over 8 ft gives 5.625 panels.
ROUNDUP(...,0) pushes any fraction to the next whole panel, because you cannot buy 0.625 of a section.
=D2+1 gives the post count — every run is bookended, so posts always outnumber panels by one.

Order the posts, then the panels; a missing post stops the whole line while a spare panel just goes back on the trailer.

Try it: interactive demo

Interactive

Enter the run length and the panel width you are pricing.

Fence run (ft)

Panel width (ft)

Variations

Add gate openings

Subtract gate width from the run before dividing so you do not buy panels for the opening.

=ROUNDUP((B2-F2)/C2,0)

Concrete bags for the posts

Two bags per post is a common rule for a 4x4 in a 10-inch hole.

=(D2+1)*2

Pitfalls & errors

Do not round the panel count down. A 5.6-panel run that gets 5 panels leaves a 5-foot gap at the end of the day.

Where two runs meet at a corner they share a post — subtract one post per shared corner from the total.

Practice workbook

📊

Download the free Fencing: Posts and Panels From a Run practice workbook

Edit the yellow run and panel-width cells; panels and posts recalculate.

Frequently asked questions

Why is it always one more post than panel?

Each panel spans the gap between two posts. Five panels in a straight line need six posts — one on each end plus the four in between.

What about slope?

On a stepped or racked run the panels follow the grade, so the count is unchanged; only the post height changes. Buy taller posts for the low end.

Stop fighting formulas. Learn them in a day.

This recipe is one of hundreds of real-world formulas we teach. Our Excel Formulas & Functions class covers lookups, logic, text, and dynamic arrays hands-on — live in Dallas–Fort Worth, Houston, Austin, Oklahoma City, Denver, or online.

See the Formulas & Functions Class

Function references: ROUNDUP