Wifi Problem or Signal Problem? How to Tell Which One Is Slowing You Down

"The wifi is slow" is the most common sentence in home internet, and half the time it is wrong. Not the slow part. The wifi part.

A cellular modem has two separate links, and they fail for different reasons. Fix the wrong one and you will rearrange your living room for nothing. This guide shows you how to tell which link is the problem in about five minutes, and what to do once you know.

The two links

Link one: tower to modem. This is the cellular signal. It carries your internet from the network to the modem. It is affected by distance from the tower, terrain, building materials, and what the modem is sitting next to.

Link two: modem to your devices. This is wifi. The modem creates a wifi network, and your laptop, phone, and TV connect to it. It is affected by distance and walls between the modem and each device, and by other wifi networks nearby.

Your streaming show has to cross both links. If either one is weak, the show buffers. The symptoms look identical from the couch. The fixes are completely different.

The five minute test

You need the modem and one phone or laptop.

1. Stand next to the modem. Within a few feet, nothing in between.
2. Make sure your device is on the modem's wifi, not on your phone's own cellular data. Turn off cellular data on the phone for the test if you need to be sure.
3. Do the thing that was slow. Load the video, open the big web page, start the call.
4. Now walk to the room where it was slow and do the same thing.

Then read the results.

• Slow next to the modem, slow in the far room: that is link one. The cellular signal reaching the modem is the limit.
• Fine next to the modem, slow in the far room: that is link two. Wifi is not reaching that room well.
• Fine everywhere on one device, slow on another: that is the device.
• Fine now, slow at certain times: probably a busy tower or a busy household. More below.

If it is link one: the cellular signal

The modem is not getting enough signal where it is sitting. Move the modem.

• Put it near a window.
• Try the side of the house facing the nearest town, highway, or hill with antennas.
• Put it up high. Second floor beats first. A shelf beats the floor.
• Get it away from metal, large appliances, the back of the TV, and any other router.

Test two or three spots and keep the winner. The full method is in our modem placement guide, and the reasons behind it are in what affects cellular signal.

Also try the oldest trick there is. Turn the modem off, wait thirty seconds, turn it back on. It works more often than it has any right to.

If it is link two: the wifi

The modem is getting good signal, but your device is too far from the modem or has too much in the way.

1. Reduce what is between them. Open interior doors. Move the modem out from behind furniture. Get it off the floor.
2. Move the modem closer to where you use the internet most, as long as it stays near a window. When the two goals conflict, the window wins. Strong cellular signal with slightly shorter wifi reach beats the reverse.
3. Move it up a floor. A modem near an upstairs window often improves both links at once.
4. Move the device. Sometimes the answer is that the desk goes on the other wall.
5. Use a cable where you can. The Business modem includes an Ethernet port, which takes wifi out of the picture for a desktop, a point of sale terminal, or a camera recorder.

A very large home, or one with thick interior walls, may need more than one wifi radio to cover every corner. That is true with any internet provider. It is a wifi coverage question, not a cellular one.

If it is the device

When one device struggles and everything else is fine, the network is not the problem.

• Restart the device. Yes, really.
• Forget the wifi network on the device and rejoin it.
• Check for a pending software update.
• Close the forty browser tabs. You know the ones.
• On an older device, accept that it may just be slow at everything.

If it only happens at certain times

Evenings and weekends: two things get busy at the same time. Your household, because everyone is home and streaming. And the tower, because everyone in the area is doing the same. A tower serves everyone connected to it, and demand rises and falls through the day. This is true of every cellular service.

During big local events: a festival, a game, or a holiday weekend can crowd a tower temporarily.

What you can do: make sure placement is as good as it can be, so you are getting the strongest possible link to begin with. A modem in the best window has more to work with at busy times than a modem behind the TV.

Common mix ups

"I have full wifi bars but nothing loads." Wifi bars only describe link two. You have a great connection to the modem. The modem may have a weak connection to the tower. Run the test next to the modem.

"It works in the living room but not the bedroom, so I need a better plan." No plan changes how far wifi travels through walls. That is link two.

"I moved the modem to the middle of the house for better coverage and now everything is worse." You improved link two and hurt link one. The middle of the house is the farthest point from every window. Move it back to glass.

"My phone has great signal in this spot, so the modem should too." Usually a fair guess, but your phone may be on a different network than the modem. Use it as a hint, then test the modem itself.

The quick reference

When nothing fixes it

If you have tested next to the modem in three different windows and every spot is poor, the location may simply have weak signal. Check a phone around the house. If it struggles too, the location is the limit. Our rural internet comparison is honest about when another type of service is the better tool.

If the modem will not connect anywhere, or behaves strangely even on its own charger, work through the troubleshooting checklist and then contact us through Support. Defective modems are replaced at no charge.

Frequently asked questions

Is cellular internet the same as wifi?
No. Cellular is how the modem gets internet from the network. Wifi is how your devices get internet from the modem. You use both.

Will a new plan make my wifi reach farther?
No. Wifi range is about distance and walls inside your home.

Should the modem go in the center of the house?
Only if the center of the house has a window. Signal from the tower comes first.

How often should I restart the modem?
Only when something seems off. It does not need a routine.

The bottom line

Slow internet has two suspects. Stand next to the modem and test. If it is slow there, fix the cellular link by moving the modem to glass and height. If it is fast there and slow elsewhere, fix the wifi link by clearing the path between the modem and your device.

Five minutes of testing beats a week of guessing. For the full setup picture, see How it Works.