Want to know what your internet connection is truly capable of? Plug in an ethernet cable and run an ethernet speed test. A wired connection strips away all the variables that muddy your Wi-Fi results — interference, distance, walls — and gives you a clean, honest number.
If you've been testing over Wi-Fi and wondering whether your ISP is delivering what it promises, this is how you find out. An ethernet test establishes a baseline. Everything below that baseline on Wi-Fi is the cost of going wireless.
Why Wired Connections Are More Accurate
Wi-Fi is convenient, but it introduces a layer of complexity between your device and your router. Radio waves bounce off surfaces, get interrupted by other devices, and degrade over distance. Ethernet cables don't have any of those problems. The signal goes straight from your device to your router through copper (or fiber), and what goes in comes out the other end with minimal loss.
That makes a wired speed test the gold standard for measuring your internet plan's actual performance. Most ISPs even specify their advertised speeds "up to" a certain number, and that number is measured on a wired connection.
Cable Types and What They Mean for Speed
| Cable Category | Max Speed | Good For |
|---|---|---|
| Cat 5e | 1 Gbps | Standard home use, up to 1 Gbps plans |
| Cat 6 | 10 Gbps (short distances) | Future-proofing, high-speed plans |
| Cat 6a | 10 Gbps (up to 100m) | Longer runs, pro setups |
| Cat 7 / 8 | 25–40 Gbps | Data centers, extreme power users |
For most households, Cat 5e or Cat 6 is all you need. If your internet plan is 500 Mbps or under, a Cat 5e cable won't bottleneck you. If you've upgraded to a multi-gigabit plan, make sure both your cable and your router's ethernet ports support the speed you're paying for.
How to Run an Ethernet Speed Test
- Connect your computer to the router with an ethernet cable.
- Disable Wi-Fi on the same computer — this ensures the test uses only the wired connection.
- Close other applications and pause any downloads or uploads running in the background.
- Run the test. Do it a few times at different points in the day for a reliable picture.
Troubleshooting Slow Ethernet Speeds
If your wired test results are lower than expected, the problem usually falls into one of a few categories:
- Bad cable — Ethernet cables go bad. A crimped connector or an internal break can drop your speed to a fraction of what it should be. Swap the cable before anything else.
- Wrong port speed — Some routers have a mix of Gigabit and Fast Ethernet (100 Mbps) ports. If you plugged into the wrong one, you're capped at 100 Mbps no matter what.
- Outdated network adapter — Older laptops might have a 10/100 Ethernet port instead of Gigabit. Check your device's specs.
- Router bottleneck — Budget routers sometimes can't handle their advertised speeds under real-world conditions. If your wired speed is consistently under your plan's target, the router might be the weak link.
When Should You Use Ethernet Instead of Wi-Fi?
Always test your internet speed over ethernet when you want a baseline. For devices that sit in one place — desktop computers, gaming consoles, smart TVs — a wired connection gives you faster, more consistent performance. It's also better for gaming, live streaming, and video conferencing where latency and stability matter as much as raw speed.
Wi-Fi is great for mobility. But when accuracy matters, nothing beats a good old-fashioned cable.