Fence Calculator
Work out exactly how many fence posts, rails, pickets and bags of concrete your project needs. Enter your fence length, pick a style and post spacing, and get an instant materials list, a live plan-view drawing and an optional cost breakdown — with a printable PDF report.
Material cost estimate (optional)
How to estimate materials for a fence
Three quick steps from fence length to a full materials list.
Measure the total linear footage the fence will run, and count any gate openings you'll need along that line.
Choose a picket, privacy or panel style, your post spacing (commonly 6 or 8 ft on-center), and your rail count.
Get the posts, rails, pickets or panels, concrete and fasteners needed, plus an optional cost estimate.
About the Fence Calculator
A fence build orders several materials off one measurement — posts, rails, boards and footings all scale from the same linear run — and getting the post count wrong is the single most expensive mistake, since it cascades into every other line item. This calculator works out all of it from the same set of inputs.
Post count starts with your total fence length divided by your post spacing, plus one starting post, plus one extra post for every gate opening you add. Each post-to-post span is a "bay," and rails are counted as one piece per bay per rail you've chosen — a 3-rail fence uses three rail pieces per bay. Panel-style fencing swaps this for one panel per bay instead.
For picket and privacy styles, board count divides your fence length by the board width plus the gap between boards — zero gap for a tight privacy fence, an inch or more for a picket style with light showing through. Concrete is estimated in bags per post, since most residential post footings use one to two 50 lb bags of quick-set concrete, though depth and mix always depend on your local frost line and post size. The optional cost section adds post, rail or panel, concrete and labor prices in eight currencies to turn the materials list into a project budget.
Why use this calculator?
Everything a fence build needs, from post count to a concrete planning estimate.
Enter your fence length and get an exact post count in seconds, gates already factored in.
Three fence styles with their own board, gap and panel math built in.
Posts, rails or panels, boards, fasteners and a concrete estimate in one pass.
Add post, rail, concrete and labor prices in eight currencies for a real project budget.
Everything runs in your browser. Nothing you enter is uploaded or stored on a server.
Mix feet, inches, yards, metres, centimetres or millimetres, fully usable on a phone on site.
Related construction tools
Round out the rest of your fence build and outdoor project estimate.
Frequently asked questions
Divide your total fence length by your post spacing (commonly 6 or 8 ft on-center) and add one for the starting post. A 100 ft fence at 8 ft spacing needs about 14 posts. Add one extra post for each gate opening, since a gate interrupts the run and needs its own posts on both sides.
Multiply the number of post-to-post spans (bays) by your rail count. A 2-rail fence needs two rail pieces per bay, a 3-rail fence needs three. A 100 ft fence at 8 ft spacing has 13 bays, so a 3-rail fence needs about 39 rail pieces.
Most residential wood or vinyl fence posts use one to two 50 lb bags of quick-setting concrete per post, depending on post size and hole depth. Deeper holes below the frost line, or larger posts, may need three bags. Always confirm your local frost depth and post size requirements before digging.
Divide your fence length in inches by the picket width plus the gap between pickets. A privacy fence with no gap between 5.5 in boards needs roughly 2.2 boards per linear foot. Add 5–15% extra for cuts, end adjustments and any damaged boards.
6 ft on-center is common for taller privacy fences and windy areas, since shorter spans add rigidity. 8 ft on-center is a standard, economical spacing for most residential picket and rail fences. Panel fencing is spaced to match the panel width you buy, usually 6 or 8 ft.