Fence Post Calculator USA 2026
Posts = (fence length ÷ post spacing) + 1, rails = sections × rails per section, pickets = length ÷ (picket width + gap), plus concrete per post hole.
Fence Post Calculator — the quick answer
Posts = (fence length ÷ post spacing) + 1, rails = sections × rails per section, pickets = length ÷ (picket width + gap), plus concrete per post hole.
Fence Calculator — instant results
Show calculation steps
- Posts = ⌈100 ÷ 8⌉ + 1 = 14
- Panels = ⌈100 ÷ 8⌉ = 13
- Concrete = 14 posts × 2 bags = 28
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What the Fence Post Calculator works out for your fence post job
Posts = (fence length ÷ post spacing) + 1, rails = sections × rails per section, pickets = length ÷ (picket width + gap), plus concrete per post hole.
Enter Fence length, Post spacing and Fence height and the fence post calculator returns the quantities you need to order instantly — no signup, no spreadsheet and no install. Every figure updates as you type so you can test two or three fence post scenarios before you commit to an order or a bid.
Fence post numbers this page gives you
The output is written for a real supply run: quantities and figures you can hand to a supplier or drop straight into a bid for fence post work.
- A planning figure for fence post, with the waste or contingency allowance stated.
How to estimate fence post step by step
The math behind this page is Posts = (fence length ÷ post spacing) + 1, rails = sections × rails per section, pickets = length ÷ (picket width + gap), plus concrete per post hole.. Nothing is hidden — the formula, the assumptions and the waste allowance are all printed on the page so you can re-check the result by hand.
Worked example: 100 ft fence, 8 ft spacing = 13 posts + 13 panels + 26 bags of concrete.
- Measure the fence post area or run and write down Fence length, Post spacing and Fence height.
- Enter the figures above and read the fence post result.
- Add the recommended waste allowance before you order.
- Save or download the estimate so your supplier and your crew work from the same numbers.
Fence post searches this page answers
Homeowners, DIYers and contractors reach this fence post page looking for the same handful of answers. Each of these is answered above with the formula shown:
- Fence post calculator
- How much fence post do I need
- Fence post estimator online
- Fence post quantity takeoff calculator
- Free fence post calculator app USA
- Fence post material calculator 2026
Before you order fence post: quick checklist
- Re-measure the fence post area once before ordering — a second check is cheaper than a second delivery.
- Keep the stated waste allowance in the order; cuts and breakage are normal on fence post work.
- Confirm coverage or unit size with your actual supplier — fence post pack sizes vary by brand.
More fence post planning tools
Pair this fence post estimate with the rest of BuildMate: a full calculator index, an AI planner that turns a plain-English description into a materials list, and step-by-step guides for the trade work itself.
Targeted searches: fence post calculator · how much fence post do I need · fence post estimator online · fence post quantity takeoff calculator · free fence post calculator app USA · fence post material calculator 2026
How the fence posts, rails and pickets math works
Fence Post Calculator — frequently asked questions
How deep should posts be?
1/3 of the fence height, plus 6" of gravel below the frost line.
How many pickets per panel?
About 17 for a 6-ft-tall × 8-ft-wide panel with 3/8" gaps.
How do I use the Fence Post Calculator?
Enter Fence length, Post spacing and Fence height. The fence post calculator instantly returns the quantities you need to order, along with the formula and every calculation step so you can verify the result.
How much fence post do I need?
It depends on your measurements, so run the fence post numbers above rather than using a rule of thumb. The calculator applies the standard trade formula plus a stated waste allowance, which is what stops you from coming up short mid-job.
What does the Fence Post Calculator include in its result?
It reports the quantities you need to order. The underlying formula is Posts = (fence length ÷ post spacing) + 1, rails = sections × rails per section, pickets = length ÷ (picket width + gap), plus concrete per post hole..
Is the Fence Post Calculator free, and does it work on mobile?
Yes — it's free, needs no account, and runs in the browser on phone, tablet and desktop. Nothing is installed and your saved fence post estimates stay on your own device.
Planning estimate only, produced from the formula shown above with documented assumptions. Always confirm quantities with your supplier or contractor before ordering.