Many users are familiar with the situation where the internet speed advertised by their provider doesn't match the actual page loading and video buffering. Often, the problem lies not with the service provider's connection, but with the bandwidth of your wireless connection or configuration. routerUnderstanding how to measure the actual data transfer speed within your local network and from your router to the outside world is key to diagnosing problems.
There are many ways to obtain this data, from simple online services to professional utilities that measure bandwidth between devices. In this article, we'll explore the differences between access point connection speed and internet speed, and learn how to identify bottlenecks in your network. WiFi networks.
Before undertaking complex tests, it's important to understand the current technical limitations of your equipment. Interface settings may vary, and device specifications may be updated.
⚠️ Attention: Wireless module specifications (Wi-Fi standards) and router firmware are constantly being updated. If you don't see the options described below in the menu, please consult the official documentation from your device manufacturer, as the interface may have changed.
The difference between connection speed and actual speed
Many users confuse two fundamentally different indicators. The first is link speed (Link Speed), which is the maximum theoretical speed that your device and router are currently negotiating. The second is the actual throughput available when transferring files or testing. The difference between the two can be dramatic.
For example, if your laptop is connected using the standard 802.11n With a 1x1 antenna, the link speed can reach 150 Mbps. However, due to protocol overhead, packet loss, and interference, the actual file transfer speed will rarely exceed 70-80 Mbps. It's important to understand this process to avoid over-demanding the equipment.
Furthermore, the frequency range affects the final result. In a congested apartment building, the 2.4 GHz band may show unstable results even with a strong signal due to interference from neighboring networks.
Software verification methods for Windows and macOS
The fastest way to find out your current link speed is to use the operating system's built-in tools. This method won't show your actual download speed, but it will give you an idea of the power limit your device is operating at. adapter.
In Windows, open the list of available networks, right-click the name of your active network, and select "Properties." Scroll down in the window that opens to find the line "Transmission Speed (Receive/Transmit)." This is the maximum speed for your current connection.
For users macOS you should hold down the key Option and click on the WiFi icon in the top menu bar. The drop-down list will show the line TX Rate, which is the current connection speed. Please note that this value is dynamic and may change depending on the distance from the router.
- 📶 Windows: Control Panel → Network and Internet → Network and Sharing Center → Change adapter settings → Double-click WiFi → Details.
- 🍏 macOS: WiFi menu + Option key → “TX Rate” line.
- 📱 Android/iOS: WiFi settings often display "Connection Speed" or "Link Speed" in the network details.
If you see low link speed values (for example, 54 Mbps or 72 Mbps) with a modern router, this is a sign of driver problems or interference.
Testing real-world LAN throughput
Online speed tests (Speedtest and similar apps) measure the speed of your connection to the ISP server. They don't show how fast your router can transfer data within your home. To check your actual speed, local network (LAN) and WiFi module of the router uses a method of transferring a large file.
The method is simple: connect your computer to the router via Ethernet, and the second device (laptop or phone) via WiFi. Then copy a large file (for example, a 4-5 GB movie) from your computer to the device via WiFi, or vice versa. Divide the file size in megabytes by the copy time in seconds to get the actual speed in MB/s. Multiply by 8 to get Mbps.
This method eliminates ISP influence and shows the pure performance of your equipment. If the speed is 100 Mbps over a cable but drops to 5 Mbps over WiFi, the problem is definitely with the wireless module or its settings.
☑️ Check speed by copying
Professional diagnostics with iPerf3
For engineers and advanced users, there is a gold standard for network testing - the utility iPerf3It generates dummy traffic between two devices, utilizing the channel at 100%, and produces highly accurate statistics on packet loss and jitter.
To run the test, you'll need two devices. iPerf3 is installed in server mode on one (usually a PC with a cable), and in client mode on the other (the device being tested via WiFi). Running the command creates a data stream that doesn't rely on hard drive or processor speed, measuring only the radio bandwidth.
The command to start the server looks simple:
iperf3 -sAnd the command for the client, which will load the network for 30 seconds:
iperf3 -c 192.168.1.1 -t 30Where 192.168.1.1 — this is the server's IP address. In the results, you will see a column Bitrate, which will show the actual throughput of your WiFi connection under ideal load conditions.
⚠️ Attention: During the iPerf3 test, the network will be fully loaded. Other devices in the home may experience internet access issues. Conduct the tests at times when it won't disrupt other devices in the home.
Analysis of the Impact of WiFi Standards and Frequencies
Connection speed directly depends on the standard supported by your router and client device. Older standards like 802.11g physically cannot deliver speeds higher than 54 Mbps, regardless of signal strength.
Modern routers often operate in two bands: 2.4 GHz and 5 GHz. The former offers better wall penetration, but suffers from slow speeds and high noise levels. The latter (5 GHz) offers higher speeds but suffers from faster attenuation when passing through obstacles.
The table below shows the theoretical and actual speed limits for different standards under ideal conditions:
| WiFi standard | Range | Theoret. max (Mbps) | Real speed (Mbps) |
|---|---|---|---|
| 802.11n (WiFi 4) | 2.4 / 5 GHz | 150 - 600 | 40 - 200 |
| 802.11ac (WiFi 5) | 5 GHz | 433 - 1730 | 200 - 800 |
| 802.11ax (WiFi 6) | 2.4 / 5 GHz | 600 - 9600 | 400 - 1500+ |
If your router supports WiFi 6, but the phone is connected at a low speed, check if the wide channel option (80 or 160 MHz) is disabled in the router settings.
Why is the speed lower than theoretical?
Wireless protocols use half the bandwidth for overhead data, packet delivery acknowledgement (ACK), and collision protection. Therefore, the actual speed is always approximately 50-60% of the advertised link speed.
Factors that reduce WiFi signal speed
Even with top-of-the-line equipment, speed can drop due to external factors. Physical obstacles are the main enemy of a wireless signal. Metal structures, mirrors, aquariums, and thick concrete walls with rebar can completely block the signal or reduce its quality.
Household appliances are also worth considering. Microwave ovens operating at 2.4 GHz, wireless baby monitors, and even LED string lights can create significant interference, causing packet loss and retransmissions.
The placement of your router's antennas also plays a role. If the antennas are removable, try adjusting their angle. Vertical placement usually provides better horizontal coverage, which is especially important for single-story apartments.
Frequently Asked Questions (FAQ)
Why is WiFi speed 2 times slower than cable?
This is normal for wireless networks. The WiFi protocol is half-duplex: a device cannot simultaneously receive and transmit data on the same frequency. Furthermore, a significant portion of the airtime is spent on service packets and interference control. A 40-50% speed loss compared to a wired connection is typical.
Does the number of connected devices affect the speed of one client?
Yes, it does have a direct impact. The bandwidth is divided among all active users. If one device is downloading torrents, the others will experience a bandwidth shortage, even if the ISP's internet connection is very broad.
How to check if your router is throttling your speed?
Connect your computer to the router via cable and measure your speed using Speedtest. Then connect the same computer via WiFi (while being close to the router) and repeat the test. If the difference between the cable and WiFi connection is more than 40-50%, your router's settings may not be optimized or its processor may be underpowered for high speeds.
Can an old phone slow down the entire network?
Older 802.11g devices can force the entire router into compatibility mode, reducing speeds for everyone. However, modern routers can isolate such devices. Check if "Green AP" or power saving mode is enabled, as this could limit performance.