Many users encounter a situation where they pay their internet provider for a 100 Mbps plan, but when connecting via a wireless network, the actual speed is significantly lower. This leads to confusion and questions for a technical specialist: why are we paying for 100 megabits, but getting 40 or 60? The answer lies in the physical limitations of wireless standards, airwave congestion, and the specifications of the equipment itself.
Under ideal conditions, when the router and client device are in the same room without walls, the speed should be close to that of a cable connection, at 80-95 Mbps. However, in reality, the signal travels through floors, reflects off furniture, and competes with neighboring networks. Real throughput always lower than the stated theoretical value due to the overhead of encryption protocols and data packet management.
Furthermore, the frequency range your device operates in also affects the final result. Older routers that only operate at 2.4 GHz are physically unable to provide stable data transfer at 100 Mbps in urban areas. Understanding these nuances will help you configure your equipment correctly and get the most out of your plan.
Theoretical and actual speed figures
First, let's clarify some terminology. ISPs report speeds in megabits per second (Mbps), while many download programs (torrent clients, browsers) display data in megabytes per second (MBps). The difference between these units is eightfold.: 1 byte equals 8 bits. Therefore, with a 100 Mbps plan, the maximum file download speed will be approximately 12.5 MB/s.
Wi-Fi technology is inherently half-duplex, meaning a device can't simultaneously transmit and receive data at full speed, as a cable can. Part of the channel is always occupied by service information, packet delivery confirmation, and collision protection. Therefore, even under ideal laboratory conditions Wi-Fi 4 (802.11n) rarely shows more than 60-70 Mbps payload when connecting to one client.
If your router only supports the 802.11n standard and operates in the congested 2.4 GHz band, then speeds of 40-50 Mbps will be considered technically normal for this equipment. To achieve speeds closer to 90-95 Mbps, you must have support for the standard. Wi-Fi 5 (802.11ac) or Wi-Fi 6 (802.11ax) and operation at 5 GHz.
- 📉 20-40 Mbps is a typical result for older routers (Wi-Fi 4) in an apartment with thick walls.
- 📶 50-70 Mbps is a good indicator for the 2.4 GHz band on modern equipment.
- 🚀 80-95 Mbps is an excellent result, achievable in the 5 GHz range within direct line of sight of the router.
Frequency Band Impact: 2.4 GHz vs. 5 GHz
The main factor determining your connection speed is the frequency band. The 2.4 GHz band is the most common and crowded. In an apartment building, dozens of neighbors' routers, Bluetooth headphones, wireless mice, and even microwave ovens may be connected there. Signal interference leads to constant packet re-acknowledgments and speed drops.
The 5 GHz band offers many more available channels and higher throughput. It's easier to achieve speeds approaching 100 Mbps at this frequency. However, it has a significant drawback: its range is shorter, and its ability to bend around obstacles (walls, corners) is significantly worse. The 5 GHz signal quickly fades when passing through concrete floors.
If your device (smartphone, laptop) is connected to a 2.4 GHz network, it's extremely difficult to achieve speeds above 50-60 Mbps due to the channel width. The standard channel width here is 20 MHz, which limits the maximum link speed. For a 100 Mbps plan, it's critical to use the 5 GHz band, where the channel width can be as wide as 80 MHz, providing a huge bandwidth advantage.
⚠️ Attention: Not all devices support the 5 GHz frequency. Older laptops and budget smartphones may have Wi-Fi modules that only operate in the 2.4 GHz band. In this case, even with a powerful dual-band router, you won't be able to exceed the limits of the old frequency.
WiFi standards and their bandwidth
Connection speed directly depends on the wireless generation supported by your router and client device. Standards are evolving, and each new stage brings increased speed and spectrum efficiency. It's important to understand that the connection always operates at the speed of the slowest endpoint.
If the router supports the modern standard Wi-Fi 6, but your laptop was released 10 years ago and only supports Wi-Fi 4, then data exchange will proceed according to the rules of the old standard. Below is a table showing the theoretical and practical speed limits for different WiFi generations at a provider's 100 Mbps rate.
| WiFi standard | Range | Theoretical max (Mbps) | Real speed (Mbps) |
|---|---|---|---|
| 802.11n (Wi-Fi 4) | 2.4 GHz | 150 - 300 | 20 - 50 |
| 802.11n (Wi-Fi 4) | 5 GHz | 300 - 450 | 60 - 80 |
| 802.11ac (Wi-Fi 5) | 5 GHz | 433 - 867 | 80 - 95+ |
| 802.11ax (Wi-Fi 6) | 5 GHz | 1200+ | 90 - 98+ |
As the table shows, to fully utilize the 100 Mbps plan, 802.11ac or higher is recommended. However, even Wi-Fi 4 can be maximized if the channel width is configured correctly. Routers often default to "Auto" or 20 MHz channel width, which artificially reduces speed.
What is MIMO and how does it affect speed?
MIMO (Multiple Input Multiple Output) technology allows multiple antennas to transmit multiple data streams simultaneously. If the router has two antennas and the phone has only one, the speed will be limited by the phone's capabilities. A single-stream connection (1x1) is sufficient for a 100 Mbps plan, but a 2x2 or 3x3 connection will provide stability and a safety margin.
Factors that reduce wireless connection speed
Why might my speed drop even with a modern router? There are many external and internal factors. Wall materials play a key role: drywall transmits the signal well, concrete with reinforcement transmits it poorly, and a mirror or aquarium can completely shield the signal.
The router's location is also important. If it's in a recess, behind a TV, or on the floor, the signal quality will be poor. Antennas should be oriented vertically to ensure the antenna pattern covers the entire horizontal plane of the apartment. Metal objects, microwaves, and baby monitors create significant interference.
Another important aspect is the number of connected devices. If one user is downloading a large game via torrent and another is watching a 4K video, the third device may not have enough bandwidth, even if their combined bandwidth doesn't exceed 100 Mbps. The WiFi protocol distributes airtime among clients, and when the channel is heavily loaded, latency increases and throughput decreases.
⚠️ Attention: Some smart devices (light bulbs, power outlets) only operate on 2.4 GHz and can generate background noise even when not in use. Large numbers of them can destabilize the network.
Diagnostics and measurements of actual speed
To understand your actual speed, you need to run measurements. This must be done correctly to eliminate the influence of external factors. The easiest way is to use online services such as Speedtest.net or Fast.com. However, the results may depend on the load on the testing server itself.
For more accurate diagnostics, it is recommended to use specialized applications on your smartphone, for example, WiFi Analyzer or WiFimanThey show not only internet speed but also signal strength (RSSI), noise level, and channel congestion from neighbors. The optimal signal level is considered to be between -40 and -60 dBm. Below -75 dBm, speed will drop.
☑️ WiFi Speed Test
Take measurements at different times of day. In the evening, when neighbors are actively using the internet, the airwaves may be congested, and speeds will drop. At night or in the morning, speeds can be significantly higher. It's also worth checking the cable speed by connecting your laptop directly to the router. If you get 100 Mbps via cable but not via WiFi, the problem lies with the wireless module or router settings.
Setting up your router for maximum speed
If you find that the equipment is working properly, but the speed is low, 192.168.0.1 192.168.1.1Channel
For the 2.4 GHz band, manually select channels 1, 6, or 11, after checking which channel is the least congested in an analyzer app. Channel Width should be set to 20 MHz for stability or 40 MHz for speed, if the air is clear. For the 5 GHz range, the channel width should be 80 MHz.
Recommended settings for 5 GHz:Mode: 802.11ac/n mixed
Channel width: 80 MHz
Channel: Auto (or 36-64)
Also make sure that the protocol is selected in the security settings WPA2-PSK (AES) or WPA3Using the legacy TKIP encryption protocol or WPA/WPA2 mixed mode may limit connection speed to 54 Mbps, as this is a compatibility mode for very old devices.
How do I reset my router to factory settings?
If you're confused about the settings, you can reset the router. Find the small hole labeled "Reset" on the router's body. With the router turned on, press the button with a thin object (like a paperclip) and hold it for 10-15 seconds until the indicator lights flash simultaneously. After this, the router will reboot to factory settings.
Does the version of WiFi adapter drivers affect speed?
Yes, it does. Outdated drivers may not work correctly with new encryption standards or may not support wide bandwidth. We recommend visiting the laptop or adapter manufacturer's website and downloading the latest drivers for your operating system.
Why does the speed drop as I move further away from the router?
When removed, the signal strength decreases, and the device automatically switches to a lower transmission rate (MCS index) to maintain the connection. This is normal behavior: a slower but more stable connection is better than no connection at all.
Can antivirus software cut WiFi speed?
Some antivirus programs have "network protection" modules that scan all incoming and outgoing traffic in real time. On slower devices, this can create delays and reduce overall speed. Try temporarily disabling the firewall to test.
Do I need to change my router if my tariff is 100 Mbps, but my speed is 40 Mbps?
If your router is older (single-band, without 5 GHz support), upgrading to a dual-band model with AC1200 or higher standard will provide a significant increase in speed and stability, allowing you to unlock the full potential of your plan.