WHICH CABLE DO I NEED?
For most home and office networks, Cat 6 is the sweet spot — it supports 10Gbps up to 55m and is widely available. Cat 6A is better for full 10Gbps runs up to 100m. Cat 8 is for data centre use only. Avoid Cat 5 — it's limited to 100Mbps.
Ethernet Cable Category Guide — Cat 5, 5e, 6, 6A, 7, 7A and Cat 8 Compared
This comprehensive Ethernet cable category reference compares every twisted-pair cable standard — Cat 5, Cat 5e, Cat 6, Cat 6A, Cat 7, Cat 7A and Cat 8 — covering maximum speed, bandwidth, supported distance and recommended use cases. Use this guide when cabling new offices, upgrading existing infrastructure, or specifying cable for server room and data centre installations.
How to Choose the Right Ethernet Cable
- Home network: Cat 5e is sufficient for gigabit at 100m. Cat 6 future-proofs for multi-gig.
- Office network (new install): Cat 6A is the recommended minimum for new builds — supports full 10Gbps to 100m and accommodates PoE++ powered devices without temperature issues.
- Server room / data centre: Cat 6A for copper runs up to 10Gbps. Consider DAC (Direct Attach Copper) cables or fibre for 25Gbps, 40Gbps and 100Gbps connections.
- IP cameras / PoE devices: Cat 6A or better for high-power PoE++ (90W) to avoid heat buildup in cable bundles.
Why Cable Quality Matters Beyond Speed
Higher category cables don't just support faster speeds — they also provide better alien crosstalk (AXT) rejection, crucial when multiple cables run in parallel in conduit or cable trays. Cat 6A's superior shielding and tighter twist ratios maintain signal integrity in dense installations. Poor cable quality can cause intermittent errors, increased retransmissions, and actual throughput far below the theoretical maximum — symptoms that are frustratingly difficult to diagnose.
Fibre vs Copper for Long Runs
Ethernet copper cables are limited to 100 metres (328 feet) for most categories. For longer runs, fibre optic cable is the solution: single-mode fibre supports runs of kilometres, multimode supports hundreds of metres at 10Gbps+. Fibre is immune to electromagnetic interference (EMI) — making it ideal for outdoor runs, between buildings, and in industrial environments near heavy electrical equipment.