How to check your Wi-Fi signal strength and improve it

A modern home is unimaginable without a stable wireless internet connection, which connects smartphones, smart TVs, gaming consoles, and security systems. However, users often encounter situations where a 4K video is streamed in one room, but constant buffering and connection drops occur two walls away. Understanding how radio waves propagate helps eliminate guesswork and pinpoint the source of the problem.

Checking your signal strength isn't just a matter of glancing at the bars in the corner of your smartphone screen, as this indicator often provides very rough information. A thorough diagnosis requires precise decibel readings, analyzing the noise level in the air, and taking into account the impact of physical obstacles. Only a comprehensive approach will allow you to identify bottlenecks in your local network.

In this article, we'll explore professional measurement methods used by system administrators and communications engineers. You'll learn to distinguish between a real equipment problem and temporary interference and understand when it's time to consider relocating your router or purchasing a repeater.

Interpretation of indicators and units of measurement

Most users are accustomed to assessing connection quality based on the graphical display of arcs or bars on their device's screen. This visualization method is highly subjective and provides no indication of the actual signal strength. The difference between three and four bars can be dramatic, while going from two to three may not yield any real speed gain.

For accurate diagnostics, a logarithmic scale for measuring signal strength is used, expressed in dBm (decibel milliwatt). Since we're talking about received power, the values ​​are always negative, and the rule is: the closer the number is to zero, the better the signal. For example, a value of -40 dBm is significantly better than -80 dBm, even though -80 is mathematically lower than -40.

⚠️ Attention: Don't confuse dBm (signal strength) with dBi (antenna gain). Increasing the dBi on a router's antenna can change the radiation pattern, making the signal wider, but not necessarily stronger at a specific reception point.

Understanding physical parameters allows you to objectively compare the performance of different access points. If you notice that the signal in a certain area of ​​your apartment drops below critical levels, no software tricks will help—you'll need to change the network topology or install additional equipment.

Diagnostics on Android and iOS mobile devices

Mobile devices are the most accessible tools for initially checking coverage quality in your home. In the Android operating system, access to hidden engineering menus allows you to see the exact signal strength value without installing third-party software. Simply enter a special code in the "Phone" app or use the system settings.

On iOS devices, the situation is more complicated due to the closed ecosystem. Apple doesn't provide a native way to display the dBm value in the status bar, but there are workarounds via the support menu or macros. iPhone owners often have to rely on third-party analyzer apps, which may request access to Wi-Fi data.

• 📱 Android: Go to Settings → About phone → Status or enter the code ##4636## in the dialer to access the testing menu.
• 🍏 iOS: Use monitoring mode via Mac (Option + click on the Wi-Fi icon) or set up a logger profile to collect data.
• 📶 Universal: Pay attention to the interface's response speed when moving between rooms—lags often precede a complete breakdown.

It's important to take measurements not only while stationary but also while moving. Holding a phone in your hand also acts as an obstacle to radio waves, especially at the 5 GHz frequency. Therefore, it's recommended to rotate around your body during testing to ensure that the user's body doesn't create any "dead zones."

Professional software for Windows and macOS

A detailed analysis of your computer's wireless environment requires more powerful tools than the standard Task Manager. Windows 10 and 11 operating systems provide basic information via the command line, but specialized utilities are better for creating graphs and analyzing channels. These programs scan the airwaves and display not only your network but also that of your neighbors.

One of the most popular utilities is inSSIDer or WiFi AnalyzerThey visualize channel overlap, which is critical in multi-apartment buildings. If your router is on a channel shared by five other neighboring devices, your speed will drop even with a strong signal due to collisions and packet retransmissions.

On macOS, the built-in diagnostic tools are much more comprehensive. By holding down the key Option and by clicking on the Wi-Fi icon in the menu bar, you will get to the extended menu where you can launch Wireless DiagnosticsThis tool can generate signal level graphs in real time as you walk around your apartment, allowing you to pinpoint areas of attenuation.

⚠️ Attention: Software and operating system interfaces are constantly updated. Button locations and tab names may differ in new versions of Windows or macOS. Always consult the software developer's official documentation if you can't find the information you need.

Using a laptop with professional software offers another advantage: the ability to work with external adapters. Built-in laptop Wi-Fi cards often have low sensitivity, so connecting a USB adapter with an external antenna can provide a completely different signal quality picture.

Why does the built-in laptop adapter perform worse than the phone?

Built-in Wi-Fi modules in laptops often have small antennas integrated into the screen casing and can be shielded by metal parts of the case. Furthermore, laptop drivers prioritize power saving, sometimes at the expense of signal stability, whereas phones are optimized for a constant mobile connection.

Command line and console utilities

For users who prefer minimalism or don't have permission to install programs, console commands are the ideal solution. They allow you to quickly obtain technical information about your current connection. In Windows, the most powerful tool is the utility netsh, which provides access to deep network stack settings.

To get a wireless network report, you need to run the command prompt as administrator. By entering the command netsh wlan show interfaces, you'll see detailed information, including the SSID, radio type, channel, and, most importantly, the signal strength as a percentage. While percentages are less informative than dBm, they give a general idea of ​​the situation.

netsh wlan show interfaces

In Linux distributions such as Ubuntu or Debian, the command is used iwlist or nmcli. Team nmcli dev wifi will display a list of all available networks with signal strength in real time. This is especially useful for automated monitoring scripts or quick environment scans without a graphical interface.

• 💻 Windows: Use netsh wlan show interfaces to view the status of the current connection.
• 🐧 Linux: Team iwconfig or nmcli dev wifi list will show the signal level.
• 🍎 macOS: In the terminal use /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -I.

Console-based methods are advantageous for their precision and lack of distracting graphics. However, they require memorizing command syntax. For regular monitoring, you can create a simple batch file or script that will output connection statistics on a schedule.

Hardware methods and specialized devices

When it comes to designing a network for a large office, warehouse, or multi-story home, software methods are no longer sufficient. Hardware spectrum analyzers and professional scanners come to the rescue. These devices are significantly more expensive than consumer routers, but they see what's hidden from standard Wi-Fi cards—the entire radio frequency range.

Specialized devices such as products from Fluke Networks or Ekahau, are able to distinguish a Wi-Fi signal from interference created by microwave ovens, Bluetooth headsets, or baby monitors. They create heatmaps by overlaying signal strength data on a floor plan, allowing for the ideal placement of access points.

For a home handyman, a regular router reflashed with alternative firmware can be an excellent alternative to expensive devices, for example, OpenWrt or DD-WRTSuch systems often have built-in broadcast scanning scripts that are as functional as paid PC programs.

Influencing factors and coverage optimization

Once you've measured your signal strength, the question arises: what to do with the data? Low values ​​can be caused by a variety of factors. The main enemies of 2.4 GHz Wi-Fi are physical obstacles and other electronic devices. Water contained in walls, aquariums, and even houseplants actively absorbs radio waves.

Metal structures, metal-coated mirrors, and foil insulation create a "shield" that completely blocks the signal. If your router is hidden behind a TV or inside a low-voltage panel, no powerful antenna amplifier will be able to penetrate this barrier. Moving the router to an open area often provides a greater speed boost than purchasing new equipment.

⚠️ Attention: Avoid placing the router near microwave ovens or other powerful heat sources. Microwaves generate significant interference in the 2.4 GHz band, and the heat can cause instability in the router's electronics.

The installation height should also be considered. Radio waves propagate downward from the antennas in a cone-shaped pattern. If the router is on the floor, half the signal will be lost to the neighbors below. The optimal height is 1.5–2 meters from the floor, in the central part of the apartment.

Signal level standards and table of values

To help you assess your network's condition, we've provided a detailed breakdown of dBm values. This data will help you understand whether the current situation is critical or within acceptable limits. Remember that ideal conditions rarely exist in reality, and slight fluctuations are normal.

The range of -30 to -60 dBm is considered excellent. In this zone, you'll get the maximum speed available with your provider's plan and minimal latency (ping). These are ideal conditions for online gaming, 4K streaming, and video conferencing.

Values ​​from -60 to -75 dBm are good and workable. Speed ​​may be slightly below the theoretical maximum, but for most tasks (surfing, YouTube, social media), this is more than sufficient. Problems may arise when multiple devices are connected simultaneously.

If your measurements show values ​​below -85 dBm, stable internet service is virtually impossible. In this range, packet loss can reach 50% or more. In this case, you need to either reconsider the equipment layout or implement a mesh network.

Why is 5GHz signal weaker than 2.4GHz?

The 5 GHz band has a shorter wavelength, making it more susceptible to attenuation when passing through walls and obstacles. However, it offers significantly higher data transfer rates and is less susceptible to interference from neighboring networks and household appliances.

Does the number of connected devices affect the signal strength?

The number of devices doesn't affect the physical signal strength (dBm) emitted by the router. However, it does directly impact the available bandwidth and response time. If the channel is clogged, a poor signal will appear due to slow page loading, even though the reception level may be excellent.

Can weather affect indoor Wi-Fi?

The weather outside has no direct effect, as the signal propagates indoors. However, high humidity (fog, rain) could theoretically slightly weaken the signal if it passes through open windows or thin walls, but in an apartment, this is negligible.