How to check WiFi signal strength at home?

If the internet is slow in one room, the connection keeps dropping, or devices keep switching between WiFi bands, it's worth checking your WiFi signal strength.

What is WiFi signal strength?

WiFi signal strength is most often expressed as RSSI, measured in dBm. This value is negative — the closer to zero, the stronger the signal. As a rough guide:

You shouldn't treat these values as a strict cut-off for internet quality, though. Final connection quality also depends on interference, device capability, channel width, the band used, and many other factors.

How to check WiFi RSSI?

The easiest way is to use an app that can read your current WiFi connection's parameters. Walk through the whole home and take measurements at a few characteristic spots, for example:

• by the router
• in the living room
• in the bedroom
• in the kitchen
• in the bathroom
• by the entrance
• on the second floor
• in a spot where WiFi often drops

This lets you see how the signal changes as you move through the home.

Why isn't one measurement enough?

WiFi signal is spatial. Two spots just a few metres apart can give completely different results. What matters includes walls, doors, ceilings, furniture, electronics, building construction, and router placement. So a single measurement by the router says little about WiFi quality across the whole home.

How to find WiFi dead zones?

A dead zone is a spot where the WiFi signal is very weak or the connection is unstable. The simplest way to find one is a series of measurements in different rooms. Walk through your home with your phone and watch how RSSI changes — if the value drops sharply in one area, that can point to a coverage problem.

It's even better if you can plot the measurements onto your floor plan. Then, instead of isolated numbers, you get a picture of the whole network.

Does a strong signal mean fast internet?

Not always — this is important. You can have a strong WiFi signal and still get low speed. The reasons can include:

• interference
• an overloaded channel
• router limitations
• device limitations
• a large number of users
• problems with the internet connection itself

So it's worth analysing several parameters at once.

What to do if the WiFi signal is weak?

If measurements show a weak signal in a specific spot, you have several options.

Move the router. Sometimes the simplest solution is the best one — if the router sits at the edge of the home, moving it to a more central spot can improve coverage.

Change the band. 2.4 GHz usually has longer range than 5 GHz and 6 GHz, but the newer bands can give better performance where the signal is already strong enough.

Add an access point. In a bigger home, an extra WiFi point can provide much better coverage.

Use mesh. A mesh system can be a good solution if you need WiFi across a larger area or several floors — but the individual points need to be placed correctly.

How to check WiFi on a floor plan?

You get the clearest picture when you combine measurements with the building's layout. A floor plan shows something a raw RSSI value doesn't — why the signal is weak. You might see that the problem room sits behind several thick walls or at the opposite end of the home, which lets you make a much better decision about where to place the router or an extra WiFi point.

How often should you check WiFi signal?

There's no need to measure daily. It's worth re-checking your network, though, when:

• you change router
• you add a mesh point
• you change your home's layout
• a neighbour's new network appears
• you move the router
• you start having connection problems

Summary

Checking WiFi signal strength is one of the simplest ways to find problems with a home network. Remember, though, that RSSI alone doesn't tell the whole story — it's best to analyse together:

• signal strength
• speed
• connection stability
• the band
• device location
• the layout of rooms and walls

And if you want to not just measure WiFi but also plan its placement, it's worth starting from the real floor plan of your flat or house.