Why use this calculator
Fencing is one of the biggest capital jobs on a grazing property, and most blowouts come from a short count of strainers or wire rather than from the price per post. Every corner and gateway needs a strainer assembly, long straight runs need intermediate strainers, and wire needs an allowance for tying off and joins.
This calculator counts all three, uses your own supplier prices rather than a stale national average, and shows the cost per metre so you can compare a quote from a contractor against doing the job yourself. The post spacing table shows what widening the spacing saves, which is the biggest lever you have on materials cost for a conventional wire fence.
How to use it
- Enter the fence length in metres from your farm map or measuring wheel.
- Choose a closed paddock boundary or an open run with two ends.
- Enter the number of corners and gateways, each needing a strainer. Enter the number of line wires. Enter the post spacing you plan to use.
- Enter the longest strain you will tension between strainers.
- Enter the metres of wire per roll from the roll tag.
- Enter your prices per line post, per strainer assembly and per wire roll from a current supplier quote.
What each result means
- Line posts
- Steel pickets or timber line posts between strainers at your chosen spacing, the largest item count on the order.
- Strainer assemblies
- Anchor points at corners, gateways, ends and on long straights, each with its stay and bed log or box.
- Wire length
- Metres of line wire for all wires on the fence, with 5 per cent added for ties, tails and joins.
- Wire rolls
- Wire length divided by the metres in one roll, rounded up to whole rolls to buy.
- Wire left on the last roll
- Metres of wire left over once the whole rolls you buy have covered the fence and its 5 per cent tie and join allowance, worth keeping for repairs.
- Estimated materials cost
- Posts, strainers and wire at the prices you entered, rounded to whole dollars, excluding labour and small hardware.
- Materials cost per metre
- Materials cost divided by fence length, the figure to compare against contractor quotes and other fence designs.
The formula
Sections = the larger of the corner and gateway count and fence length / longest strain rounded up (plus one for an open run's corners)
Strainers = sections for a closed loop, or sections + 1 for an open run
Post positions = fence length (m) / post spacing (m), rounded up, plus 1 for an open run
Line posts = post positions minus strainers
Wire length
(m) = fence length x number of wires x 1.05, the 5 per cent covering ties and joins
Rolls = wire length / metres per roll, rounded up
Cost ($) = line posts x post price + strainers x strainer price + rolls x roll price
How this number is used in practice
Australian rural fencing is usually quoted per metre or per kilometre, and contractor rates vary widely with terrain, access, soil and whether they supply materials. Knowing your materials cost per metre lets you split a quote into labour and materials and compare like with like.
Steel Y pickets at 4 to 6 metre spacing with 2.5 mm high tensile plain wire are the common standard for cattle, while sheep fences often use prefabricated netting with a plain or barbed top wire, which this calculator does not count as line wire.
Strainers are where fences fail. A poorly set strainer lets the whole run go slack within a season, so most state department fencing guides suggest box or angle stays on every corner, gateway and at intervals along long straights. Flood crossings, creek lines and steep gullies need extra strainers and posts that no simple count can predict, so walk the line before ordering.
Many Australian landholders are also eligible for fencing assistance after bushfire or flood, or for fencing waterways, through state and catchment programs.
Worked examples
1,000 m paddock boundary, 4 corners, 4 wires, posts at 5 m, $9 posts, $180 strainers, $250 rolls of 1,500 m
196 line posts, 4 strainers, 4,200 m of wire in 3 rolls, about $3,234 of materials or $3.23 per metre.
2,400 m straight boundary run, no corners, 5 wires, posts at 5 m, strainers every 400 m
474 line posts, 7 strainers, 12,600 m of wire in 9 rolls, about $7,776 of materials.
600 m two-wire electric paddock, 4 corners, posts at 10 m, $6 posts, $120 strainers, $90 rolls of 500 m
56 line posts, 4 strainers, 1,260 m of wire in 3 rolls, about $1,086 of materials.
When people use it
- Ordering posts, strainers and wire for a new paddock subdivision
- Splitting a contractor quote into labour and materials
- Comparing plain wire, barbed and electric designs on cost per metre
- Budgeting boundary fence replacement with a neighbour
- Costing waterway or remnant vegetation fencing for a grant application
Tips
- Walk the line before ordering. Creek crossings and gullies need extra posts and strainers.
- Add 5 to 10 per cent spare posts for rock, breakage and changes of direction.
- Put strainers at every change of direction greater than a few degrees, not just at square corners.
- Talk to your neighbour before replacing a boundary fence; state dividing fence laws usually share the cost.
- Ask about fencing assistance for waterways, bushfire or flood recovery through your state or catchment authority.
What it assumes, and where it stops being accurate
- Line posts are counted at even spacing along the whole length, with strainer positions taken out.
- Each corner and gateway gets one strainer assembly; gates themselves, hinges and latches are not costed.
- Wire length adds 5 per cent for ties, tails and joins. Netting, droppers, insulators and energisers are not counted.
- Terrain, rock and soil type, which change post spacing and strainer needs, are not modelled.
- Prices are materials only and exclude labour, freight, machinery hire and GST unless you include them in the prices.
Terms used on this page
- Strainer
- A heavy anchor post or assembly that line wires are tensioned against.
- Line post
- An intermediate post or steel picket that holds wires at height between strainers.
- Stay
- A diagonal brace that stops a strainer post leaning under wire tension.
- High tensile wire
- Plain steel wire with higher breaking strain, allowing longer strains and wider post spacing.
Questions people ask
- What is a strainer assembly?
- A strainer assembly is the heavy anchor that line wires are tensioned against, usually a large strainer post with a diagonal stay and a bed log, or a box assembly of two posts and a brace. They sit at every corner, gateway and end of a fence and at intervals along long straight runs.
- How far apart should strainers be on a straight run?
- For high tensile plain wire on flat ground many fencers go 300 to 500 metres between strainers, and up to about 800 metres on very straight, even country. Hilly or rough ground needs shorter strains. Enter your chosen longest strain and the calculator adds intermediate strainers where the length needs them.
- What post spacing should I use?
- Conventional plain wire fences in Australia commonly use steel pickets at 4 to 6 metres. Barbed wire fences for cattle are often closer. Electric fences can run 10 to 20 metres between posts on flat ground. Wider spacing saves materials but may need droppers to keep wires evenly spaced.
- Why does a closed boundary need fewer posts than an open run?
- A closed loop ends where it starts, so the first and last post are the same post. An open run has two separate ends, each needing its own strainer. The difference is one post position and one strainer, which matters little on long fences but noticeably on short ones.
- Does this include the cost of labour?
- No. It covers posts, strainers and line wire at your prices. Contract fencing labour in Australia is usually quoted per metre and varies widely with terrain, access and design, so get two or three local quotes and compare them against the materials cost per metre shown here.
Use this with
Fencing Materials Calculator answers one part of the question. These pick up where it stops: Fence Post and Rail Calculator, Stocking Rate Calculator, Cost Per Hectare Calculator and Water Tank & Dam Volume Calculator.
Where these figures come from
Figures and rules on this page follow Australian law and ATO guidance.
- NSW Department of Primary Industries. Farm budgets, drought feeding, fencing, farm dam and soil water guidance
- Agriculture Victoria. Extension notes on feeding livestock, farm water supplies and soil moisture
- Meat & Livestock Australia. Livestock nutrition, drought feeding and supplementary feeding research
Fencing Materials Calculator produces an estimate for general information. It is not financial, tax, medical, legal or engineering advice. read the full disclaimer. Spotted a wrong number? Report it and it gets fixed. The form picks up this calculator and the inputs you used.