The internet is fine but the Wi-Fi is slow: how to tell

People call about slow internet when the outside line is working and the last thirty feet of radio inside the house is the weak link. A cable test takes two minutes and sorts the two cases. Here is how to run it and what to do with the answer.

How do you tell a line problem from a Wi-Fi problem?

Take a laptop that has an Ethernet port, or a small adapter if it does not. Plug it into a spare port on your router. Turn the laptop's Wi-Fi off so the test cannot cheat. Run a speed test, then run it twice more and write down the three results. Then unplug the cable, turn Wi-Fi on, stand in the same spot and test three more times.

The wired number is the most your line can show to that router. High Desert's plans list up to 500, up to 800 and up to 1 Gig down and up to 200 up (hdiss.net, read 10/15/26), and a test never reaches an up-to figure exactly, so do not expect a perfect match. What matters is the gap. If wired is respectable and Wi-Fi is a small fraction of it, the line is doing its job. If both are low, the cause is upstream and you should call. The speed test guide has the full method.

Why does Wi-Fi fall off so much inside a house?

Wi-Fi is a radio signal and every wall takes a piece of it. Wood framing and drywall take a little. Stucco with wire mesh, brick, a masonry fireplace, a water heater closet, a mirror and a refrigerator take a lot. Metal siding and metal roofs on shops block signals almost completely, so a router in the house rarely reaches a metal building.

Distance matters too, but not in a straight line. A router can look strong in the next room and drop off sharply two walls away. The higher radio bands, 5 GHz and 6 GHz, carry more data but get through walls less well than 2.4 GHz does. The band guide explains the trade.

What else slows Wi-Fi without touching the line?

Four things come up most. First, the router sits low, in a cabinet or behind a TV. Second, the device is far from the router and on 2.4 GHz, which is the crowded band that baby monitors, microwaves and neighbors' routers also use. Third, an older router or an old laptop that only supports earlier Wi-Fi standards, which cap out far below what a newer one does, no matter how fast the plan. Fourth, too many devices asking for data at once, which is a sharing problem rather than a signal problem; see how many devices is too many.

A slow result on one device and a fine result on the others points at that device. Restart it, forget the network and join again, and check for updates. The one-device article goes through the steps.

What fixes work, in order of effort?

Try them in that order. The first two cost nothing, and they fix a good share of the calls.

• Move the router: higher, central, in the open. See where to put your router.
• Join the 5 GHz network when you are in the same room or one wall away.
• Run a cable to the TV, the desktop and the work computer. See Ethernet for the things that matter.
• Update the router's firmware and restart it; the FTC advises keeping router software current (FTC, read 10/15/26).
• If the house is large or has thick walls, think about a mesh system. See whole-home Wi-Fi and mesh.

When is it the line after all?

If a wired test is poor on every try, at different hours, with only one device connected, then Wi-Fi is not the cause. Restart the equipment in the order the restart article lists, wait a few minutes, and test again. Do not climb to the antenna or touch the outdoor radio or its cable; if the problem persists, call and a technician comes.

Write down the wired results and the time you took them before you call. It saves the office a round of questions. A person answers at 775-575-9593 every day from 9 to 5, and the slow internet checklist covers the rest.