How Far Can an Ethernet Cable Go? | Distance Limits Explained

Standard copper Ethernet cables have a maximum channel length of 100 meters (328 feet), including patch cords, to maintain reliable signal integrity.

That 100-meter limit is the hard cap for twisted-pair Ethernet under the TIA/EIA-568 standard. Whether you’re wiring an office or connecting a home gaming setup, exceeding this distance risks packet loss, speed drops, or a link that won’t establish at all. The practical breakdown is 90 meters of solid-core horizontal cabling inside the wall plus up to 10 meters of stranded patch cables at the ends.

But the story isn’t quite that simple. The same cable run that handles 1 Gbps at 100 meters may choke at 10 Gbps over half that distance — and what you’re connecting, the category you choose, and how you measure all matter. Here’s what the spec actually means for your installation.

The 100-Meter Rule: Permanent Link vs. Channel

The Ethernet standard defines the 100-meter limit as the entire channel — the full signal path from the switch port to the end device. That includes the solid copper run plus every patch cord, coupler, and wall jack in between. Structured cabling splits it into two parts: up to 90 meters of permanently installed solid-conductor cabling, and up to 10 meters of stranded patch cables in total.

If you measure only the in-wall cable and skip the patch cords, you’ll hit link problems earlier than expected. A 95-meter wall run with 8 meters of patch cable on each end puts you at 111 meters total — above the spec and likely unstable.

Maximum Distance by Cable Category

Different categories change what speeds you can run at a given length. Here’s the per-category breakdown:

The table shows a real gotcha: Cat6 can support 1 Gbps across the full 100 meters but limits 10 Gbps to about 55 meters (and sometimes just 37 meters in noisy environments). If you’re planning future 10 Gbps upgrades, Cat6a is the safer bet for the full distance.

What Happens When You Exceed the Limit

Going beyond 100 meters doesn’t immediately break the connection — but it degrades signal quality in ways you’ll notice. The cable experiences higher attenuation (signal loss), which can cause the link to drop from Gigabit to 100 Mbps, introduce retransmission delays, or fail to negotiate a connection at all. The effect gets worse with cable that’s thinner than 23 AWG or installed near electrical interference.

If you genuinely need to cover a longer distance — say, running Ethernet across a warehouse or between buildings — the proper fix is an active device like a network switch, media converter, or Ethernet extender. A switch regenerates the signal and resets the 100-meter counter on the far side. For runs beyond 300 feet, you’re also looking at fiber optic cable as a better solution.

For most home setups, a standard 50- or 75-foot pre-terminated cable works fine. If your run falls near the 100-meter limit, measuring the full path before buying is essential. Our roundup of the best 70-foot Ethernet cables can help you find one that matches your distance and speed needs.

How to Measure Your Ethernet Run Correctly

The most common mistake is measuring only the wall-to-wall cable and forgetting the patch cords at each end. To measure your actual channel length: start from the switch or router port, follow the cable through every patch panel, wall jack, and coupler, and stop at the device’s Ethernet port. That’s your total. Add every foot of patch cable — a 5-foot cord at each end adds 10 feet you might not have accounted for.

For best results, keep the cable within manufacturer bend-radius limits (typically 4x the cable diameter), avoid running parallel to high-voltage power lines, and use solid copper rather than Copper Clad Aluminum (CCA) cable for permanent installations. Temperature above 40°C can further reduce effective range, especially for PoE runs where heat buildup matters.

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