Fence Post Calculator

    Count line posts, corner posts and brace assembly posts for a fence run from its length, fence type and terrain — and price the posts before you order.

    Your numbers

    The run

    One mile is 5,280 ft. Measure with a wheel, GPS or plat map.

    Sets the default post spacing for this style of fence.

    Rough ground needs tighter spacing to keep wire at the right height. Varies by region — use your own figure where you have one.

    Anchors and cost

    Every direction change that the wire pulls against.

    Each end post and each side of a gate opening needs its own brace.

    Steel T-post or small wood line post, delivered. Varies by region — use your own figure where you have one.

    Treated wood post heavy enough to hold tension, plus rail. Varies by region — use your own figure where you have one.

    5,280 ft of barbed wire (conventional) at 11.9 ft spacing

    484 posts total

    Line posts (incl. spares)
    468
    Corner, end and brace posts
    16 across 10 braces
    Post cost for the run
    $3,394 ($0.64/ft)
    • Anchor posts are 16 of 484 posts but 10% of the post cost — corners, gates and ends are where a fence budget actually goes.
    • This counts posts only. Wire, staples, clips, brace rails, brace wire, gates and labor are separate line items.
    • Tighten spacing further anywhere cattle press the fence — a lane, a corner approach, or along a water gap.
    Show the math
    1. Spacing used14 ft base × 0.85 (Rolling ground) = 11.9 ft
    2. Line posts5,280 ft ÷ 11.9 ft + 1 = 445 posts
    3. Brace assemblies(4 corners × 2) + 2 ends = 10 assemblies
    4. Anchor posts4 corner + 2 end + (10 assemblies × 1 extra brace post, corner/end post shared) = 16 posts
    5. Spare line posts445 × 5% = 23 posts
    6. Total posts445 + 16 + 23 = 484 posts
    7. Line post cost468 × $6.50 = $3,042
    8. Anchor post cost16 × $22.00 = $352
    9. Cost per foot$3,394 ÷ 5,280 ft = $0.64/ft

    Assumptions this calculator used

    Nothing here is hidden. Change any figure you have better local data for.

    • Leave at 0 to use the spacing implied by fence type and terrain. Source: USDA NRCS Fence Conservation Practice Standard 382.

      ft
    • Total posts in one H-brace assembly, including the shared corner/end post. Single H-brace = 2; double H-brace on long pulls or loose soil = 3. Source: Standard H-brace construction, extension fencing guides.

      posts
    • Breakage while driving, rock refusals and re-sets. Source: Field allowance.

      %

    How to calculate fence post

    A post count is two separate numbers added together. Line posts come straight out of run length divided by spacing, with one extra because a run of ten spaces needs eleven posts. Anchor posts — corners, ends, gates and the brace assemblies behind them — do not scale with length at all; they scale with how many times the fence changes direction or stops.

    Line posts = (length ÷ spacing) + 1
    Brace assemblies = (corners × 2) + ends
    Anchor posts = corners + ends + (brace assemblies × posts per brace)

    Worked example

    One mile of barbed wire on rolling ground with four corners and two ends: spacing is 14 ft base × 0.85 for rolling = about 12 ft, so 5,280 ÷ 12 + 1 = 441 line posts. Corners give 4 × 2 = 8 brace assemblies, plus 2 at the ends, for 10 assemblies. Each assembly is the corner or end post (already counted) plus one shared brace post, so that is 10 extra brace posts on top of the 4 corner and 2 end posts — 16 anchor posts. At 5% spares that is roughly 480 posts on the order.

    Common mistakes

    • Forgetting the plus-one post. Dividing length by spacing counts spaces, not posts. On a short run of pens that error repeats at every fence line.
    • Bracing a corner in only one direction. A corner pulls two ways and needs an assembly running back down each fence line, or it walks out of the ground.
    • Using flat-ground spacing on broken country. Wire that follows the ground on paper sags through every dip in reality, and cattle find it.
    • Setting steel where tension lands. T-posts are line posts. Ends, corners and gates need wood set deep, no matter how good the steel is.

    Post spacing and posts per mile by fence type and terrain

    Line posts only — corner, end and brace posts are counted separately. Posts per mile includes the plus-one post on the run.

    Post spacing and line posts per mile by fence type and terrain
    Fence typeFlat spacingBroken groundLine posts / mile (flat)
    Barbed wire, 4-5 strand14-16 ft8-10 ft331-378
    Net / woven wire14 ft10 ft378
    Net wire with barbed top12-14 ft8-10 ft378-441
    High-tensile electric, permanent40-50 ft25-30 ft106-133
    Polywire, temporary electric50-60 ft35-40 ft89-106
    Pipe / continuous panel20-24 ft16-20 ft221-265
    Corral or working pen fence8 ft8 ft661

    Guides that use this calculator

    Questions ranchers ask

    How far apart should fence posts be for barbed wire?

    Conventional barbed wire on flat ground is usually set with line posts 12 to 16 feet apart, tightened to 8 to 10 feet on rolling or broken ground and in high-pressure areas like a corner approach or a lane. Stays or droppers between posts let you widen spacing without letting cattle spread the wires.

    How many posts do I need per mile of fence?

    At 16 ft spacing a mile takes about 331 line posts; at 12 ft it takes about 441; at 20 ft it takes about 265. Add corner, end and brace posts on top of that, plus one extra line post per run because a run of n spaces needs n+1 posts.

    How far apart can electric fence posts be?

    Because a hot wire is a psychological barrier rather than a physical one, permanent high-tensile electric fence commonly runs 30 to 50 ft between posts on flat ground, and temporary polywire on step-in posts can go 40 to 60 ft. Tighten spacing wherever terrain would let the wire sag to grazing height or lift over a dip.

    What is an H-brace and how many posts does it take?

    A single H-brace uses two posts plus a horizontal brace rail — three pieces — and is used at every end, corner and gate. A double H-brace, used on long pulls or in loose soil, adds a third post and a second rail. Corners generally need two brace assemblies, one running each direction from the corner post.

    How deep should fence posts be set?

    A general rule is one third of the post length in the ground, so an 8 ft post is set roughly 2.5 to 3 ft deep. Corner and brace posts go deeper — commonly 3.5 to 4 ft — because they carry the whole tension of the run, and in frost country every post should be below the frost line.

    Do I need a brace at every rise and dip?

    Not a full H-brace, but you do need an anchor. Wire pulls up out of a dip and down over a rise, so a dip needs a post tied down or a longer post set deep, and a crest needs a heavier post to carry the downward load. Skipping this is the most common reason a new fence goes slack in the first year.

    Are steel T-posts or wood posts better?

    T-posts are cheaper, faster to drive, and fine as line posts. Wood is what you want anywhere the fence is anchored — ends, corners, gates and brace assemblies — because steel will not hold against tension. Most working fences mix them: wood at every stress point, steel between.

    How much does the corner and brace count add to a job?

    On a short run it dominates the bill. A 300 ft fence with two ends only (no corners) might need about 21 line posts and 4 brace-assembly posts — roughly a sixth of the posts, and a much larger share of the cost since brace posts run three to four times the price of a line post. On a mile of straight fence with two ends, braces are under 1% of the count. Always price the corners separately.

    Fencing new ground for cattle you have not bought yet?

    Fence gets built for a stocking rate, and stocking rate depends on what class of cattle you run. Settle the herd plan first, then browse verified lots on Agrilot with documented weights and classes so the fence you build in spring matches the cattle you actually turn out.

    Sources

    Spacing and brace guidance from USDA NRCS Conservation Practice Standard 382 (Fence), Kansas State University and University of Missouri Extension fence construction publications. Post prices are user-supplied and vary widely by region and treatment class.

    These figures are estimates for planning purposes only. Forage production, feed quality, weather and market conditions vary by region and by season, and a calculator cannot see your ground. Confirm any decision that carries real money against your own records and your local extension office, which can give site-specific recommendations for your county.