Wired vs Wi-Fi: how to tell where your slowdown is
The fastest way to find a broadband problem is to compare wired and Wi-Fi. Plug a device into the router with an Ethernet cable and run a speed test, then run the same test over Wi-Fi. If wired is fast but Wi-Fi is slow, it’s a Wi-Fi problem. If both are slow, it’s your line, router or provider.
Last updated: · Written by The NetSorted team
This one test saves a lot of wasted effort. Before changing anything, find out where the slowdown is.
The test
- Plug a laptop or computer into the router with an Ethernet cable.
- Run the speed test and note the result.
- Disconnect the cable, connect to Wi-Fi on the same device, and run it again.
What the result tells you
- Wired fast, Wi-Fi slow → it’s a Wi-Fi problem. Work through fix slow Wi-Fi or better Wi-Fi in every room.
- Both slow → it’s not Wi-Fi. It’s your line, router or provider — see why is my internet so slow?.
No cable to hand?
Test on Wi-Fi right next to the router, then again in the room that struggles. A big gap between the two is a coverage problem; similar (low) speeds in both points to the line.
Once you know where the problem is, you can fix the right thing instead of guessing.
Frequently asked questions
How do I know if it’s my Wi-Fi or my broadband that’s slow?
Plug a device into the router with an Ethernet cable and run a speed test, then run the same test on Wi-Fi. If wired is fast and Wi-Fi is slow, it’s your Wi-Fi. If both are slow, the problem is your line or provider.
What if I can’t plug in with a cable?
Test as close to the router as possible on Wi-Fi, then test in the problem spot. A big difference between the two points to a Wi-Fi coverage problem rather than your line.
My wired and Wi-Fi speeds are both low — what now?
That means it’s not Wi-Fi. Check for an outage, restart your router, and if you’re well below your plan speed, report a fault.
Published and last updated — see dates above.