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Fence length for acreage

Given acres (and shape), estimate perimeter feet and miles, then optionally add cross-fences and multiply by wire strands for material ballpark.

When to use

Use this when quoting woven wire, barbed wire, or electric fence for a new paddock sized in acres — before you walk the line with a wheel.

Square enclosures minimize perimeter for a given acreage; long rectangles need more fence. Cross-fences add interior runs.

Calculator

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How this is calculated

sq_ft = acres x 43,560. For a square, side = sqrt(sq_ft), perimeter = 4 x side. For ratio r = L/W: W = sqrt(sq_ft / r), L = r x W, perimeter = 2(L+W). Cross-fence length approx shorter side x count.

sq_ft = acres x 43,560
square: side = √sq_ft; perimeter = 4 x side
ratio r: W = √(sq_ft / r); L = r x W; perimeter = 2(L+W)
total_fence ≈ perimeter + cross_count x min(L,W)
wire_ft = total_fence x strands

Corners, gates, roll-out waste, and terrain extras are not included — add 5-10% for real orders.

Worked example

10-acre square: √435,600 ≈ 660 ft side → perimeter 2,640 ft (0.50 mi). Four strands → 10,560 ft of wire.

Same 10 acres at 2:1 rectangle: W ≈ 466.7 ft, L ≈ 933.4 ft → perimeter ≈ 2,800 ft.

Limits / assumptions

Assumptions: axis-aligned rectangle; cross-fences span the shorter dimension; no ditch or timber detours.

Limits: creek meanders and diagonal braces need field measure.

Responsibility: planning aid — confirm with a wheel or GPS track before buying rolls.

FAQ

Why does a square use less fence?

Among rectangles, a square has the minimum perimeter for a fixed area.

Does this include gates?

No — subtract gate opening from fence line and add brace posts separately (see the post calculator).

Electric vs barbed strand count?

Enter the number of energized or barbed wires you will hang; multiply fence length by that N.

What about round pens?

Perimeter of a circle = 2πr; convert acres to radius first (r = √(sq_ft/π)). This page focuses on paddock rectangles.