Slow Wi-Fi on a laptop: why the Internet is slow and how to fix it

You open your browser and the pages take forever to load. Video on YouTube constantly buffers and online games lag. At the same time, the Internet works fine on the phone or tablet. Is this a familiar situation? If your laptop suddenly starts to slow down after Wi-Fi, there can be dozens of reasons - from banal router settings to hardware problems with the network card.

In this article we will look at all possible reasons for slow Wi-Fi on a laptop, including specific cases for different operating systems (Windows 10/11, macOS, Linux). You'll learn how to diagnose the problem, which settings to check first, and when to call a professional. And also - why sometimes the speed drops only on specific sites or at certain times of the day.

Don’t rush to blame the provider: in 80% of cases the problem lies in the settings of your device or router. Let's sort it out in order.

1. Speed Check: Is the Wi-Fi Problem Really?

Before you dig deeper, make sure that this is the problem. wireless connection, and not on the Internet at all. Here's how to do it:

• 📱 Test on other devices: Connect your smartphone, tablet or other laptop to the same Wi-Fi. If the speed is low everywhere, the problem is with the provider or router. If only on a laptop, we look for the reason in it.
• 🔌 Cable check: Connect your laptop to the router via Ethernet-cable. If the speed has increased, the Wi-Fi adapter or its settings are to blame.
• 🌐 Speed tests: Take the test for Speedtest.net or Fast.com. Compare the results with your provider's tariff. For example, if you have a tariff 100 Mbit/s, and the test shows 10 Mbit/s - something is clearly wrong.

Important: carry out tests at the same time of day. In the evening, the speed may drop due to the congestion of the provider’s network - this is normal. But if the decline is observed around the clock, it’s time to act.

2. Router settings: 5 parameters that kill speed

The router is the “brains” of your home network, and incorrect settings can slow down Wi-Fi on your laptop. Go to your router control panel (usually at 192.168.1.1 or 192.168.0.1, login/password on the sticker on the back) and check:

• 📡 Wi-Fi operating mode: If the router is operating in 802.11b/g, maximum speed is limited 54 Mbit/s. Switch to 802.11n/ac (or ax, if supported).
• 🔄 Channel and channel width: Automatic channel selection often fails. Manually set the channel with minimal interference (use utilities like Wi-Fi Analyzer for Android). Channel width for 2.4 GHz put 20 MHz, for 5 GHz — 40 or 80 MHz.
• 🔒 Encryption type: WEP Not only is it unsafe, but it also slows down the network. Use WPA2-PSK or WPA3.
• 📶 Transmission power: In some routers you can increase the signal strength (optional Transmit Power). But be careful: the maximum power may overheat the device.
• 🔄 Qos (Quality of Service): If enabled, it may artificially limit the speed for some devices. Try turning it off.

After making changes, be sure to restart the router (unplug for 30 seconds). If you are not sure about the settings, reset the router to factory settings (Reset button on the rear panel) and configure again.

3. Drivers and settings of the Wi-Fi adapter on the laptop

If the problem is only on the laptop, the culprit may be network adapter or its drivers. Here's what to check:

For Windows:

1. Open Device Manager (Win + X → Device Manager).
2. Find a section Network adapters and open it.
3. Right-click on your Wi-Fi adapter (the name may contain Wireless, Wi-Fi, Intel, Realtek, Broadcom) and select Update driver.
4. If the update does not help, remove the driver (Remove device) and reboot your laptop. Windows will install the driver again.

For macOS:

On MacBook Wi-Fi problems are often solved by resetting SMC And NVRAM:

1. Выключите MacBook.
2. Нажмите и удерживайте Shift + Control + Option + кнопку питания в течение 10 секунд.
3. Отпустите клавиши и включите ноутбук.

For Linux:

Check which driver is used for the Wi-Fi adapter with the command:

lspci -k | grep -A 3 -i network

If the driver is proprietary (for example, broadcom-sta), install it via Terminal:

sudo apt install firmware-b43-installer

How to find out the model of a Wi-Fi adapter in Windows?

Open Command line (Win + R → cmd) and enter: ipconfig /all

Find the line Description next to Wireless network adapter - this is the model of your adapter.

4. External interference: why neighbors steal your speed

Your Wi-Fi operates on the same frequency as dozens of other networks around you. If the channel is overloaded, the speed drops. Here's how to check and fix it:

• 📊 Ether Analysis: Install the application on your smartphone Wi-Fi Analyzer (Android) or NetSpot (iOS/macOS/Windows). It will show which channels are occupied by neighboring networks.
• 🔄 Change channel: In the router settings (Wireless Settings) select the least busy channel. For 2.4 GHz optimal channels 1, 6, 11 (they don't intersect).
• 🚫 Sources of interference: Microwaves, cordless phones DECT, Bluetooth devices and even USB 3.0 hubs can cause interference. Try turning them off or moving the router further away.

If you live in an apartment building, consider purchasing a router that supports 5 GHz or Wi-Fi 6 (802.11ax) - they are less susceptible to interference.

5. Viruses, background processes and system limitations

The laptop may slow down not because of Wi-Fi, but because overloaded system. Here's what to check:

• 🦠 Viruses and malware: Run your laptop with antivirus (Kaspersky, Dr.Web, Malwarebytes). Some viruses use your internet for mining or DDoS attacks.
• 📥 Background updates: Windows Update, macOS Software Update or even Steam can download gigabytes in the background. Check Task Manager (Ctrl + Shift + Esc) on the tab Network.
• 🔧 Speed limits: B Windows Bandwidth reservation can be enabled (20% of the speed is given to the system). Disable this:

  gpedit.msc → Конфигурация компьютера → Административные шаблоны → Сетевые → Пакет планировщика QoS → Ограничить резервируемую пропускную способность

  Set value 0%.

• 🎮 Game lags: If it slows down only in games, check the settings NAT in the router. The optimal type for online games NAT Open or Moderate.

Also worth checking DNS servers. The default is to use your provider's DNS, which can be slow. Try replacing them with 1.1.1.1 (Cloudflare) or 8.8.8.8 (Google):

1. Open Control Panel → Network Connections.
2. Right click on your Wi-Fi, select Properties → IP version 4 (TCP/IPv4).
3. Check the box Use the following DNS server addresses and enter new values.

6. Hardware problems: when is it time to take your laptop to a service center?

If none of the above helps, the problem may be gland:

Symptom	Possible reason	Solution
Wi-Fi disconnects periodically, speed fluctuates	Overheating of the network card or router	Clean the laptop from dust, check the temperature (HWMonitor). Provide ventilation for the router.
Low speed only on large files	Problems with the Wi-Fi adapter buffer	Update the driver or replace the adapter (for older laptops).
The laptop does not see the network 5 GHz	An old Wi-Fi adapter (for example, Intel Centrino Wireless-N 1000)	Buy an external USB adapter that supports 5 GHz (For example, TP-Link Archer T4U).
Speed drops when running on battery	Energy-saving settings limit Wi-Fi performance	B Device Manager Disable the adapter turn off permission to save power.

If the laptop is older than 5 years, its Wi-Fi adapter may simply not meet modern standards. In this case, only replacing the adapter or using an external USB module will help.

Check the temperature of the laptop and router|Update the laptop BIOS (carefully!)|Test the laptop with a different router|Try connecting to Wi-Fi in a different place (for example, in a cafe)-->

7. Specific cases: why only YouTube, Steam or torrents slow down

Sometimes the problem only appears on certain services. Let's look at the most common cases:

• 🎥 YouTube/Netflix slows down, but the speed is normal: Video services may artificially limit quality when detecting a VPN or proxy. Disable VPN and clear browser cache (Ctrl + Shift + Del).
• 🎮 Lags in online games with good ping: Check Packet Loss (packet loss) through Command line:

  ping google.com -n 50

  If the loss is >5%, the problem is with the router or provider.

• 📥 Torrents download slowly: The provider may limit P2P traffic. Try changing the port in the torrent client settings or use VPN.
• 💻 Websites load slowly, but speed tests are normal: Possibly enabled Proxy or settings changed Hosts. Check the file C:\Windows\System32\drivers\etc\hosts for extra entries.

If the problem is with only one site, check its availability through services like DownForEveryoneOrJustMe. Perhaps the site is down or blocked by your provider.

FAQ: Frequently asked questions about slow Wi-Fi on a laptop

❓ Why is Wi-Fi slow only at night?

In the evening and at night, provider networks are overloaded due to the large number of users. This is called "peak load". Also, background system updates (Windows, antiviruses) can run at night. Check Task Manager on the tab Network.

❓ The laptop shows a good Wi-Fi signal, but the Internet does not work. What's the matter?

This may be a problem with DHCP - a protocol that assigns IP addresses. Try manually setting the IP in the connection settings (for example, 192.168.1.100 with mask 255.255.255.0 and gateway 192.168.1.1). If it doesn't help, reboot the router.

❓ Wi-Fi is slow on a laptop, but fast on a phone. What to do?

Most likely, the problem is in the drivers or settings of the laptop's Wi-Fi adapter. Update the driver, disable power saving for the adapter in Device Manager and check if the mode is enabled 802.11b/g in the router settings (it limits the speed).

❓ Can an antivirus slow down Wi-Fi?

Yes, some antiviruses (for example, Avast, Norton) scan network traffic in real time, which can slow down your connection. Try temporarily disabling network protection in your antivirus settings or adding your browser to exceptions.

❓ How to check if someone is stealing my Wi-Fi?

Go to your router control panel (192.168.1.1) and find the section DHCP Clients List or Connected Devices. All connected devices will be listed there. If you see strangers, change your Wi-Fi password to a more complex one (use WPA2-PSK or WPA3).

If after all the checks the problem remains, the provider may be to blame. Call support and ask them to check the line. Sometimes the cause of slow Wi-Fi is problems on the operator's side, which can only be solved with their help.