28/05/2026
RJ45 Cable Wiring Color Code (T568A & T568B)
Correct cable termination is one of the fundamentals of reliable network infrastructure.
Whether you work in telecom, IT, CCTV, or data centers — understanding T568A and T568B standards is essential 👇
📘 What are T568A and T568B?
These are the two most common wiring standards used for terminating Ethernet cables with RJ45 connectors.
The difference is mainly in the arrangement of the green and orange wire pairs.
📌 T568A Color Order
1️⃣ White/Green
2️⃣ Green
3️⃣ White/Orange
4️⃣ Blue
5️⃣ White/Blue
6️⃣ Orange
7️⃣ White/Brown
8️⃣ Brown
📌 T568B Color Order
1️⃣ White/Orange
2️⃣ Orange
3️⃣ White/Green
4️⃣ Blue
5️⃣ White/Blue
6️⃣ Green
7️⃣ White/Brown
8️⃣ Brown
⚡ Which standard is more common?
👉 T568B is the most widely used standard in commercial networks today.
👉 T568A is often preferred in government or residential installations.
🔄 Important rule:
Use the same standard on both ends of the cable unless you intentionally create a crossover cable.
🛠️ Common mistakes during crimping
Incorrect wire order
Untwisting pairs too much
Poor pin contact
Using wrong cable category or connector type
Pro Tip:
Always test the cable after crimping using a cable tester to avoid hidden connectivity issues.
Small details in cabling make a huge difference in network stability and performance.
Which standard do you use most often — T568A or T568B?
