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Cable runs, total cable, fittings and posts for a code-compliant cable railing.
With these inputs:
| Result | Value |
|---|---|
| Cable runs per section | 10 cables, 2.95 in apart |
| Cable to order (+10%) | 507 ft |
| End fittings | 60 (30 tensioners + 30 fixed ends) |
| Posts | 13 (4 end/corner, 9 intermediate) |
| Materials (kit) | $2,586 – $5,511 |
| Section length (average) | 13 ft 4 in |
| Installed by a contractor | $4,138 – $9,369 |
| Installed per linear foot | $103 – $234 |
Assumes 1/8 in stainless cable, a top rail, 3 in maximum spacing between cables and the posts at the spacing chosen; cables are tensioned per straight section, so every corner is an end for the cables on both sides. End and corner posts take thousands of pounds of combined cable tension — use posts rated for cable or brace wood posts well. Cable railing is not allowed in some jurisdictions and on some stairs; check before you order.
Cable railing has to stop a 4 in sphere even when the cables flex, so the runs are set about 3 in apart and the posts no more than 4–5 ft apart. This works out how many cables your guard height needs, how much cable to order, how many end fittings and tensioners, and how many end, corner and intermediate posts — plus a planning cost for the kit or an installed system.
With cables about 3 in apart, a 36 in guard needs 10 cables and a 42 in guard 12. The gap stays under 3 in so that a 4 in sphere still cannot pass when a cable is pushed sideways.
Most systems want posts no more than 4 ft apart, some allow 5 ft. Wider spacing lets the cables deflect too far under a push and fail the 4 in sphere test.
For a typical 40 ft, three-section deck railing this calculator's planning range is roughly $65–$140 per linear foot for a kit with metal posts and $100–$230 per linear foot installed. Wood posts bring the kit price down; custom stainless pushes it up. It is two to four times the cost of a basic wood railing.
It is accepted in most US jurisdictions when it passes the 4 in sphere test under load and the posts resist a 200 lb outward force. Some areas restrict horizontal infill because children can climb it, so check with your building department first.
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