One of the most common mistakes on cabling projects is running out of termination hardware mid-job. Ordering too few means delays; ordering too many ties up budget. This guide gives you a straightforward method to calculate exactly what you need — with a sensible waste allowance built in.
Understanding the Two Termination Points
Every structured cabling run has two ends:
- The outlet end — typically a keystone jack mounted in a wall plate or surface box
- The patch panel end — either a keystone jack in a modular patch panel, or a punch-down panel with integrated IDC terminations
RJ45 field-termination connectors (also called "pass-through" or "crimp" connectors) are used when you're terminating a cable directly into a plug — for example, making a custom-length patch cord on site. They are not used at keystone or patch panel terminations.
Step 1: Count Your Cable Runs
Start with the total number of individual cable runs in your project. Each run = one cable from the patch panel to an outlet. If you have a 24-port patch panel fully populated, that's 24 runs.
Step 2: Calculate Keystone Jacks
Each run requires two keystone jacks: one at the outlet and one at the patch panel (if using a modular panel). Add a 10% waste allowance for damaged or failed terminations.
Formula: Keystone jacks = (Number of runs × 2) × 1.10
Example: 48 runs → (48 × 2) × 1.10 = 106 keystone jacks
If you're using a punch-down patch panel (non-modular), you only need keystone jacks at the outlet end:
Formula: Keystone jacks = Number of runs × 1.10
Example: 48 runs → 48 × 1.10 = 53 keystone jacks
Step 3: Calculate RJ45 Connectors (for Field-Made Patch Cords)
If you're making patch cords on site rather than using pre-made patch cords, each patch cord requires two RJ45 connectors. Add a 15% waste allowance — crimp connectors are more prone to failure during termination than keystone jacks.
Formula: RJ45 connectors = (Number of patch cords × 2) × 1.15
Example: 48 patch cords → (48 × 2) × 1.15 = 111 RJ45 connectors
Pro tip: For most commercial projects, pre-made patch cords are faster to deploy and more reliable than field-terminated plugs. Reserve field-termination connectors for custom lengths that pre-made cords can't cover.
Step 4: Don't Forget Wall Plates and Surface Boxes
Each outlet location needs a wall plate or surface-mount box to house the keystone jack(s). Count the number of outlet locations (not runs — a dual-port wall plate covers two runs at one location) and order accordingly.
Quick Reference Table
| Runs | Keystone jacks (modular panel) | Keystone jacks (punch-down panel) | RJ45 connectors (if making patch cords) |
|---|---|---|---|
| 12 | 27 | 14 | 28 |
| 24 | 53 | 27 | 56 |
| 48 | 106 | 53 | 111 |
| 96 | 212 | 106 | 221 |
Matching Cable Category to Termination Hardware
Always match your keystone jacks and RJ45 connectors to your cable category. CAT6A cable must be terminated with CAT6A-rated jacks and connectors — using CAT6 hardware on CAT6A cable will limit your channel to CAT6 performance and void any channel certification.
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Find keystone jacks, RJ45 connectors, patch panels, and wall plates in our Accessories collection, and browse our full Network Cable range for cable to match. Need a project quote? Contact our team with your run count and floor plan.