Ultimate DIY Ethernet Cable Guide: T568A vs T568B Wiring, Crimping Tips, and Cable Specs
- Amiee
- 4 days ago
- 3 min read
Making your own Ethernet cable is surprisingly easy! Just pick a T568B standard, grab a crimping tool and some connectors, and in minutes you're wired. Not sure whether to use crossover or straight-through? It depends on your devices. And remember: Cat5e is fine for most homes, but Cat6 or higher is better for speed!
Why Make Your Own Ethernet Cable?
Have you ever struggled with Ethernet cables that are too short, too expensive, or just not quite right? Learning to make your own is a game-changing skill that can save you time and money. All you need is a crimping tool, a length of twisted pair Ethernet cable, and a few RJ45 connectors—then you're good to go!
Tools and Materials You’ll Need
RJ45 Connectors – For terminating the cable ends
Ethernet Cable (Cat5e, Cat6, etc.) – Typically 8-conductor twisted pair
Crimping Tool – To secure the wires into the RJ45 connector
Wire Stripper or Utility Knife – For removing cable jacket
Cable Tester – To check if the connection is correct (optional, often used by IT pros; you can also test by connecting two devices directly)
T568A vs T568B Wiring Standards
Ethernet cables contain eight color-coded wires. There are two common wiring standards: T568A and T568B.
What’s the Difference?
T568A and T568B differ only in the positions of the orange and green wire pairs. Both perform identically in terms of signal transmission. If both ends use the same standard, the cable is a straight-through type. If each end uses a different standard, it becomes a crossover cable.
So how do you know which one to choose?
For most home networks: Go with T568B—it's the most common in Taiwan and North America.
Government or legacy systems: Might require T568A.
Repairing or extending an existing cable: Match the original wiring.
Not sure? Use T568B—it’s broadly compatible and widely used.
T568A / T568B Pinout Comparison (Left to Right)
Pin | T568A | T568B |
1 | Green/White | Orange/White |
2 | Green | Orange |
3 | Orange/White | Green/White |
4 | Blue | Blue |
5 | Blue/White | Blue/White |
6 | Orange | Green |
7 | Brown/White | Brown/White |
8 | Brown | Brown |
While functionally equivalent, T568B is more commonly used in Taiwan and the U.S.
Crossover vs Straight-Through Cables
Straight-Through: Both ends use the same standard (e.g., T568B–T568B). Common for connecting a computer to a router or switch.
Crossover: One end uses T568A, the other T568B. Used to connect two computers or two network devices directly.
Tip: Most modern devices support Auto MDI-X, so straight-through cables usually work either way.
Step-by-Step Wiring Instructions
Strip the Outer Jacket: About 2 cm of outer sheath using a wire stripper or utility knife.
Untwist and Align Wires: Arrange the wires according to T568A or T568B.
Trim the Ends: Cut the wires to the same length (about 1.2 cm).
Insert into RJ45 Connector: Ensure each wire reaches the end and is in the correct slot.
Crimp It: Use the crimp tool to secure the connector.
Test the Cable: Use a cable tester or plug it into devices to check connectivity.
Ethernet Cable Category Comparison
Category | Bandwidth | Max Speed | Max Length | Best Use Case |
Cat5e | 100 MHz | 1 Gbps | 100 m | Home, basic office networking |
Cat6 | 250 MHz | 1 Gbps (up to 10 Gbps for <55 m) | 55–100 m | High-speed LAN |
Cat6a | 500 MHz | 10 Gbps | 100 m | Data centers, large installations |
Cat7 | 600 MHz | 10 Gbps | 100 m | High EMI environments |
Cat8 | 2000 MHz | 25–40 Gbps | 30 m | Server rooms, ultra-fast usage |
Cable Material and Environment Guide
UTP (Unshielded Twisted Pair): Most common, no shielding, flexible, affordable. Best for homes and small offices.
STP (Shielded Twisted Pair): Foil or braided shielding to reduce EMI. Ideal for industrial or high-noise areas.
FTP (Foiled Twisted Pair): Foil-wrapped per wire pair. Great for medium-to-large office installs or dense cabling.
Best Material by Scenario
Home/Office: Cat6 UTP or Cat6a FTP—great for stable 1G–10G performance.
High-EMI environments (e.g. server racks): Use STP or FTP and ensure proper grounding.
Extreme temperature or outdoor use: Choose cables with heat-resistant PVC or LSZH (Low Smoke Zero Halogen) jackets for durability and safety.
Distance Limitations & Solutions
Standard Max Length: 100 meters for Cat5e–Cat6a. Beyond this, signal loss occurs.
To Extend Range:
Use hubs or switches every 100 meters.
Switch to fiber optics for longer distances (up to kilometers).
Use PoE extenders for low-power devices like IP cams.
Reminder: Always assess your network layout and power needs to ensure stability.
