Free Calculator · Published November 2026
Fence Picket Calculator for Boards, Posts, and Rails
A fence picket calculator divides fence length by one picket plus one gap. An 80 foot run, a 5.5 inch picket, and a 0.25 inch gap is 166.957 pickets at three decimals. Posts are one more than the number of bays at the spacing you type. Nothing on this page is a price.
Built by SubcontractorHub — the software contractors use to quote, finance, and run every job.
Book a DemoHow the Fence Picket Calculator Divides the Run
Inches of fence, divided by inches of pitch. Pitch is width plus gap. Rails are bays times the rails you type.
5.5, 0.25, 8, and 2 are example inputs so the arithmetic is visible. They are not a required picket or a required spacing.
Pitch 5.750 in. Pickets 166.957, which rounds up to 167 boards. Posts 11. Bays 10. Leftover 0.000 ft. Rails 20.000.
All calculations are estimates based on historical information and should be verified by the user.
Important: the widths are yours
All calculations are estimates based on historical information and should be verified by the user. This tool is provided as a free service for planning purposes only and is not a substitute for a professional assessment, a supplier quote, or applicable local code requirements.
A Count, Not a Fence Price
Installed price, by material and by the foot, stays on the fence cost calculator. This page does not borrow those ranges and does not add a dollar box. Board feet of a rail, if you already know the cross section, stay on the board foot calculator. The two pages answer different questions. One is how many pieces. The other is what the job might cost.
Worked run
Length 80 feet is 960 inches. Picket 5.5 inches plus gap 0.25 inches is a pitch of 5.75 inches. 960 ÷ 5.75 = 166.957 pickets at three decimals. Ordering whole boards means 167. Post spacing 8 feet divides 80 with nothing left over, so bays are 10 and posts are 11. Two rails per bay is 20 rails. Change any input and the line changes. None of those inputs is a code minimum.
| Step | Example |
|---|---|
| Pitch | 5.75 in |
| Pickets at three decimals | 166.957 |
| Whole boards, rounded up | 167 |
| Bays | 10 |
| Posts | 11 |
| Rails | 20 |
How should the material list read?
- Fence length in feet.
- Picket width and gap, and the pitch those two add up to.
- Pickets at three decimals, and the whole-board count after rounding up.
- Post spacing, bay count, post count, and leftover feet.
- Rails per bay, and the rail total.
- A note that price was not calculated here.
Why the last gap matters
Dividing by width plus gap assumes a gap travels with every picket, including a gap after the last board. A layout that starts and ends on a picket, with one fewer gap, uses slightly fewer inches of pitch. If the row looks one board high, that is the reason. Gates are not subtracted. Measure the picket run between posts, not through the gate opening, or the count includes a leaf you are not building. Corner posts shared by two runs should be counted once if you add two lengths. This page does that only when you enter one length.
What the Division Does Not Decide
The pitch is one picket plus one gap, in inches. Fence length in inches divided by that pitch is the picket count. An 80 foot example with 5.5 and 0.25 is there so 960 divided by 5.75 can be checked by hand. Those two widths are not a stock size. If the boards in the truck are 5 inches and the gap you want is 3/8 inch, type 5 and 0.375. The line will change. Nothing in the formula prefers the example.
Posts are bays plus one, and bays are the length divided by the spacing you type, rounded down. Leftover feet are shown and are not turned into another bay. If you want a post at the leftover end anyway, add it. Rails are bays times the rails per bay you type. Two rails on the example is not a code minimum and not a maximum. Three rails is just a different input.
Gates, corners, and shared posts are outside the single-length division. Measure the picket run between the posts that will actually carry pickets. Do not run the length through a gate leaf you are buying as a separate unit. If two runs share a corner post, count that post once when you add the two results. This page will not do that addition for you, because it only sees one length at a time.
Price stays on the fence cost page. This count does not know chain link from cedar, and it does not print a dollar. Board feet of a rail, once you know thickness and width, belong on the board foot page. Bring the picket count, the post count, and the rail count to the estimate as quantities. Do not multiply them by a price this page never stored.
Frequently Asked Questions
How are the pickets counted?
Fence length in inches, divided by picket width plus the gap, both in inches. An 80 foot run with a 5.5 inch picket and a 0.25 inch gap is 960 divided by 5.75, which is 166.957 pickets at three decimals. Those widths are example inputs, not a standard picket.
How are posts and rails counted?
Bays are the fence length divided by the post spacing you type, rounded down. Posts are bays plus one. Rails are bays times the rails per bay you type. If the length does not divide evenly, the leftover feet are shown and are not turned into an extra bay.
Does this page price the fence?
No. This page is a count. The fence cost calculator is the page for installed price. This fence picket calculator does not print a dollar figure and does not assume a picket width, a post spacing, or a rail count.
What if the last gap should be omitted?
The division uses width plus gap for every picket, which leaves a gap after the last picket as well. If your layout has one fewer gap than pickets, the count will be slightly high. Shorten the length or widen the pitch until the row matches the boards you will actually nail.
Save the Picket Count
The picket count, the post count, and the rail count belong on the job record, next to the price from the other page.
Get a Free DemoAll calculations are estimates based on historical information and should be verified by the user. This tool is provided as a free service for planning purposes only and is not a substitute for a professional assessment, a supplier quote, or applicable local code requirements.