Ethernet Cable Color Coding: Standards and Best Practices

Wire Pair Colors Inside the Cable

Every standard Ethernet cable — whether Cat5e, Cat6, or Cat6A — contains exactly eight conductors organized into four twisted pairs. The TIA/EIA-568 standard defines the color coding for these pairs, and it is universal across all cable categories.

Each pair consists of two wires: one solid color and one white wire with a colored stripe (or a colored wire with a white stripe, depending on the manufacturer). The four pairs are:

These four pair colors are the same regardless of which wiring standard you follow. The difference between T568A and T568B is which pair goes to which pins in the RJ45 connector — not the colors of the pairs themselves.

When you strip back the jacket and untwist the pairs, you should see exactly these eight wires. If any color is missing, duplicated, or unfamiliar, the cable may be non-standard telephone wire or a proprietary cable that is not suitable for Ethernet.

T568A vs T568B Pin Color Order

The wiring standard you follow determines which colored wire goes to which pin in the RJ45 connector. Both T568A and T568B use the same four pair colors — the only difference is that the orange and green pairs swap positions.

Notice that pins 4-5 (blue pair) and pins 7-8 (brown pair) are identical in both standards. The only change is the swap of the orange pair (pins 1-2 in T568B, pins 3-6 in T568A) and the green pair (pins 3-6 in T568B, pins 1-2 in T568A).

When using pass-through connectors like the EZ-RJ45, you can visually verify the wire color order through the front of the connector before crimping. This is the most reliable way to catch color sequence errors before they become a failed termination.

Ethernet Jacket Color: No Official Standard

This is one of the most common sources of confusion in networking. The TIA/EIA-568 standard defines the wire colors inside the cable and the pin assignments at the connector, but it says nothing about jacket color. There is no official standard that dictates what the outer color of an Ethernet cable should mean.

That said, the industry has developed informal conventions over decades of use. These conventions are not mandatory, but they are widely enough recognized that following them makes your installation easier for the next person to understand.

Common Jacket Color Conventions

The following table lists the most widely recognized jacket color conventions. These are industry practices, not standards — your organization can define its own color scheme. What matters is consistency within your environment and clear documentation.

Using Color Coding for Cable Management

In a well-organized network rack or network closet, color coding provides instant visual identification of cable purpose. You can identify a cable's function from across the room without reading a single label. Here are the most common strategies.

Color by Function / VLAN

This is the most popular approach. Assign a jacket color to each logical function in your network:

• Blue — Workstation data connections
• Yellow — PoE devices (access points, IP phones, cameras)
• Red — Server / infrastructure uplinks
• Green — Guest network or DMZ
• White — Management network (switch-to-switch, out-of-band management)

When every port on a patch panel is connected by color-coded patch cables, you can trace which VLAN or function a cable belongs to at a glance. This is invaluable during troubleshooting — you immediately know which cables are safe to touch and which are production-critical.

Color by Floor or Zone

In larger buildings, some teams assign a unique color per floor or physical zone. All cables serving the second floor might be orange, while third-floor cables are purple. This simplifies tracing when you have multiple floors landing in the same MDF (main distribution frame).

Color by Cable Category

If you are running both Cat5e and Cat6 in the same environment, using different jacket colors for each category prevents accidentally patching a Gigabit device into a Cat5e run. This is especially useful during transitional upgrades when legacy and new cable coexist.

Patch Cable Color Coding Strategy: Example Scheme

Here is a practical color scheme for a typical office network with 1-3 racks. This is not the only valid approach — the important thing is to define a scheme, document it, and stick to it.

Post this scheme on the inside of the rack door or at the top of the rack so that anyone who opens the cabinet knows the system immediately. A laminated card with the color assignments saves time for every technician who touches the rack.

Labeling vs Color Coding

Color coding and labeling solve different problems, and the best installations use both.

Labels: The primary identification

Cable labels carry specific information that color alone cannot: port number, VLAN ID, destination room, patch panel position. A properly labeled cable tells you exactly where it goes without tracing. Labels are essential on every permanent run and should be placed at both ends of the cable, close to the connector.

Color coding: The visual supplement

Color gives you category-level identification at a glance. You do not need to read a label to know that a yellow cable is PoE and a red cable is a server uplink. When troubleshooting under pressure, the ability to visually scan a rack and identify cable types instantly is a significant time-saver.

For permanent horizontal runs through walls and ceilings, the jacket color is typically chosen based on cable category or fire rating rather than function. Color coding for function is most practical on patch cables in the rack and at the desk, where you can easily swap colors to match your scheme.

Shielded Cable Identification

Identifying whether a cable is shielded (STP) or unshielded (UTP) matters for both termination and connector selection. Shielded cables require shielded connectors — using an unshielded connector on shielded cable defeats the purpose of the shield and can actually make interference worse.

How to tell STP from UTP

• Read the jacket print. The cable type is printed on the jacket. UTP cables say "UTP." Shielded cables use designations like STP, FTP (foil twisted pair), S/FTP (screened foil twisted pair), or S/UTP (screened unshielded twisted pair).
• Feel the cable. Shielded cables are noticeably stiffer and heavier than UTP due to the foil or braided shield beneath the jacket.
• Strip the jacket. If you cut back the outer jacket, you will see a metallic foil layer (FTP) or a braided metal mesh (STP) wrapping the wire pairs. UTP cables have no metallic layer — just the four twisted pairs and possibly a plastic spline separator.

When terminating shielded cable, use connectors specifically designed for STP, such as the Shielded EZ-RJ45 Cat6 or the Cat6A/7 Shielded Connector. These connectors have a metal housing that makes contact with the cable shield and maintains the shielded path all the way to the device.

Reading the Cable Jacket Print

Every Ethernet cable has text printed along its jacket that tells you exactly what the cable is. Learning to read this print is more reliable than jacket color for identifying cable specs. Here is what each marking means.

Cable category

The print will include the cable category: Cat5e, Cat6, or Cat6A. This determines the cable's maximum bandwidth and supported Ethernet speed. See our Cat5e vs Cat6 vs Cat6A comparison for the full breakdown.

Fire rating

The fire rating indicates where the cable can legally be installed:

• CM (Communications) — General-purpose, suitable for in-wall horizontal runs on the same floor.
• CMR (Communications Riser) — Rated for vertical runs between floors (risers). Flame-retardant to prevent fire from traveling between floors.
• CMP (Communications Plenum) — Rated for air-handling spaces (plenum areas above drop ceilings and below raised floors). Low-smoke jacket required by code in these spaces. CMP cable is always more expensive than CMR or CM.

A higher-rated cable can always be used in a lower-rated space (CMP in a riser, CMR in a general run), but never the reverse. Using CM cable in a plenum space is a fire code violation.

Conductor type

The jacket may say Solid or Stranded. Solid conductors are used for permanent horizontal runs (wall-to-patch-panel). Stranded conductors are more flexible and used for patch cables that get plugged and unplugged frequently. The connector you use should match the conductor type — the contact geometry is different.

Wire gauge

You may see a gauge marking like 24 AWG or 23 AWG. Cat5e typically uses 24 AWG conductors, while Cat6 and Cat6A use 23 AWG (thicker). The gauge matters for connector selection — a Cat5e connector designed for 24 AWG may not properly seat a thicker 23 AWG Cat6 conductor.

Shielding type

If the cable is shielded, the print will include a designation like UTP, FTP, STP, S/FTP, or S/UTP. UTP is the most common in commercial environments. Shielded cable is used in industrial, hospital, and data center environments where electromagnetic interference is a concern.

Example jacket print

This tells you: Cat6, 23 AWG, 4 pair, unshielded (UTP), riser-rated (CMR), and third-party verified. Every piece of information you need to select the right connector and verify code compliance is printed right on the cable.