How to estimate a chain link fence
A chain link fence is fabric stretched between terminal posts — every end, corner and gate post — with line posts and a top rail holding it up in between. Measure each side, subtract gate openings, and you have the fabric footage. Fabric comes in 50-ft rolls; the top rail comes in 10 ft 6 in pieces that slip together for about 10 ft of coverage each.
Worked example — 100 ft of 4-ft fence, straight, no gate: 100 ÷ 50 = 2 rolls. 100 ÷ 10 = 10 top rails. 100 ft ÷ 10-ft maximum spacing = 10 spans, so 9 line posts between 2 terminals. Each end post takes one tension bar with 3 bands, so 6 bands, 2 brace bands, 2 rail end cups and 8 carriage bolts.
Posts: sizes, spacing and lengths
Residential line posts are 1-5/8 in outside diameter and terminal posts 2-3/8 in (Merchants Metals). Line posts go no more than 10 ft apart, and each side is divided evenly — a 31-ft side gets four spans of 7 ft 9 in. Terminal posts stand 2 in taller than the fabric so the rail end cup clears it; line posts stand 2 in lower so the loop cap and rail sit on top. Master Halco sizes holes at about 8 in × 30 in for terminals and 6 in × 18–24 in for line posts; go deeper where frost or soft soil demands it.
| Fabric height | Line post (min) | Terminal post (min) | Bands per tension bar |
|---|---|---|---|
| 3 ft | 4' 6" | 5' 4" | 3 |
| 42 in | 5' | 5' 10" | 3 |
| 4 ft | 5' 6" | 6' 4" | 3 |
| 5 ft | 6' 6" | 7' 4" | 4 |
| 6 ft | 7' 6" | 8' 4" | 5 |
Fittings per terminal post
The fittings all hang off the tension bars, and a corner post takes two of everything because fabric ends there from both directions:
| Fitting | End or gate post | Corner post |
|---|---|---|
| Tension bar | 1 | 2 |
| Tension bands (4-ft fabric) | 3 | 6 |
| Tension bands (6-ft fabric) | 5 | 10 |
| Brace band + rail end cup | 1 each | 2 each |
| Carriage bolt (5/16 × 1-1/4 in) | 1 per band | 1 per band |
| Dome cap | 1 | 1 |
The common shortcut of “one band less than the height in feet” undercounts 3-ft and 42-in fabric: Master Halco's table calls for at least 3 bands per bar. Ties go every 12 in on line posts and every 24 in on the top rail, and a bottom tension wire gets a hog ring about every 2 ft.
Gates
Chain-link gates are sold by the opening — the space between the inside faces of the two gate posts. Standard single gates fit 36, 39, 42 and 48 in openings, and double drive gates 10 or 12 ft (Master Halco). Every gate needs two terminal posts, two post hinges and two frame hinges per leaf, and a fork latch; double gates add a drop rod. Hang gates at least 2 in off the ground.
Concrete per post
With 4 in of gravel under the post and concrete stopping 3 in below grade, an 8 × 30 in terminal hole holds about 0.61 cu ft of concrete — 2 × 50-lb bags of Fast-Setting — and a 6 × 24 in line-post hole about 0.26 cu ft, or 1 bag. Master Halco's older “two 60-lb sacks per hole” fits the terminal holes only; line posts need less than half that.
Mistakes to avoid
- Forgetting that corners take two tension bars, two sets of bands and two rail end cups.
- Counting line posts as total length ÷ 10 rounded up — that includes the terminal positions and overbuys posts.
- Running straight over a slope: where the grade changes more than 15 in per 100 ft, add a corner-post assembly.
- Assuming chain link makes a pool barrier: CPSC guidance limits the mesh to 1.25 in square (or slats that close it to 1-3/4 in) and the fence to 48 in tall.
- Digging before calling 811, or setting posts right on the property line instead of about 4 in inside it.
Building wood or vinyl instead? Use the fence calculator. Comparing quotes? Try the fence cost calculator. Common sizes: 100 ft, 4 ft high, 300 ft rolls, 6-ft fittings.