Why is my Wi-Fi router losing internet speed? And how can I fix it?

Have you connected your laptop or smartphone to Wi-Fi, but pages take forever to load, videos are slow, and online games are laggy—even though everything works fine over a cable? This is a common problem faced by every second user. There are several reasons why speeds drop. Wi-Fi router There could be dozens: from banal network overload to hidden settings that even experienced administrators don't know about.

In this article, we will not only list the possible culprits of slow internet, but also show How to accurately determine the source of the problem — with step-by-step instructions, tests, and setup recommendations. You'll learn why even a new router with support Wi-Fi 6 What can choke your speed, how neighbors and appliances can influence it, and when it's not the router's fault, but your ISP's. Finally, a quick diagnostic checklist and an FAQ with answers to the most frequently asked questions.

Spoiler: in 60% of cases, the problem is resolved in 5 minutes with simple steps—without replacing equipment or calling support. Let's start with the most obvious.

1. Checking the real speed: where are megabits lost?

Before you dig into your router settings, you need to understand where exactly does the speed drop occur?To do this, conduct three tests:

1. Cable speed (connect your computer directly to your modem/router with an Ethernet cable).
2. Wi-Fi speed on the same device, standing next to the router.
3. Speed ​​on another device (for example, a smartphone) at the same point.

Use services Speedtest.net, Yandex Internetometer or Fast.com (from Netflix). Important: Test on one server and at one time to avoid any impact on your provider's load.

Critical momentIf your cable speed is lower than your ISP promises, resolve that issue first. Setting up Wi-Fi is pointless if the bottleneck is on your ISP's end. In 20% of cases, "slow Wi-Fi" is the result of speed limits imposed by the provider due to exceeding the traffic limit or technical work.

2. Channel congestion: who is stealing your internet?

A Wi-Fi router is like a road with a limited number of lanes. If too many devices are connected at once, the speed for each one drops. But the problem isn't just the number of devices, but also what are they doing.

For example, one device downloading torrents or updating Windows can "eat up" 90% of the bandwidth, leaving crumbs for others. And older routers (especially those with Wi-Fi 4 standard) are physically unable to distribute the load evenly.

• 📱 Smartphones and tablets: background app updates, cloud backups (iCloud, Google Photos).
• 💻 Computers: torrents, online games, 4K streaming, OS updates.
• 🎮 Game consoles: downloading games (eg Call of Duty: Warzone weighs over 200 GB!).
• 📺 Smart TV and media players: automatic download of updates, video buffering.
• 🔌 Smart Home: surveillance cameras (especially in cloud mode), voice assistants.

How to check, who is loading the network:

1. Go to the router's web interface (usually at 192.168.0.1 or 192.168.1.1).
2. Find the section DHCP Clients List, Connected Devices or Local area network.
3. See which devices are connected and how much traffic they consume (if the router supports monitoring).

Disable background updates on smartphones | Pause downloads on PC | Limit torrent speed to 50% of the bandwidth | Turn off auto-updates for games on consoles-->

⚠️ Attention: some routers (eg. TP-Link Archer C6 or Asus RT-AC66U) have a built-in QoS (Quality of Service) — a traffic prioritization function. If configured incorrectly, it may artificially limit the speed for some devices. Check the settings in the section Bandwidth Control or Traffic Management.

3. The Impact of Concentration: How Neighbors and Home Appliances Interfere with Wi-Fi

Your router operates on a specific frequency - 2.4 GHz or 5 GHz (or both, if supported Dual-Band). These frequencies are shared by all nearby devices, including neighbors' routers, microwaves, cordless phones, and even some light bulbs. The more "noise" on a frequency, the worse the connection speed and stability.

On frequency 2.4 GHz There are only 3 non-overlapping channels (1, 6, 11), and if your router is on the same channel as 5 neighboring ones, they will interfere with each other. 5 GHz There are more channels, but the signal penetrates walls worse.

How to check the airtime load:

• Download the app Wi-Fi Analyzer (Android) or NetSpot (Windows/macOS).
• Run a scan - it will show you which channels are busy and how busy they are.
• If there are many other networks on your channel, change it in the router settings (section Wireless Settings → Channel).

Which channel should I choose on 2.4 GHz?

If your neighbors are occupying channels 1, 6, and 11, try intermediate channels (such as 3 or 9), but keep in mind that they overlap. Ideally, switch to 5 GHz if your devices support it.

Unexpected sources of interference:

• 🔌 Microwave ovens: operate at a frequency of 2.4 GHz and completely “jam” Wi-Fi during warm-up.
• 📞 DECT cordless phones: especially older 2.4 GHz models.
• 💡 Smart bulbs and sockets: some models (eg Xiaomi Mi Home) create background noise.
• 🚗 Dash cams and radars: may interfere if the router is located next to a window on a busy street.

⚠️ AttentionIf you live in an apartment building with 10-20 Wi-Fi networks on each floor, even changing the channel may not help. In this case, consider switching to Mesh systems (For example, TP-Link Deco or Google Nest Wi-Fi), which automatically select the least congested frequencies.

4. Outdated router settings: what needs to be updated?

Many users don't access their router settings for years, and in the meantime, firmware becomes outdated, Wi-Fi standards are updated, and old settings begin to slow down the network. Here are the key settings to check:

4.1. Wi-Fi operating mode (802.11 b/g/n/ac/ax)

If your router supports Wi-Fi 5 (802.11ac) or Wi-Fi 6 (802.11ax), but the settings are set to 802.11b/g/n, you lose up to 50% of the speed. On the other hand, if you set only 802.11ac, old devices (eg, iPhone 6 or Samsung Galaxy S5) will not be able to connect.

The best option:

• For 2.4 GHz: 802.11n (if all devices are modern) or 802.11g/n (for compatibility).
• For 5 GHz: 802.11a/n/ac or 802.11a/n/ac/ax (if the router supports Wi-Fi 6).

4.2. Channel Width

On frequency 5 GHz You can select the channel width: 20 MHz, 40 MHz, 80 MHz or 160 MHzThe wider the channel, the higher the potential speed, but the less stable it is—especially in apartment buildings.

4.3. Router firmware

Outdated firmware may contain speed-limiting bugs. Check the version in the section System Tools → Firmware Upgrade and update if a new version is available. Important: Do not interrupt the update process or turn off the router!

5. Hardware limitations: when the router can't handle modern speeds

If your router is older than 5 years, there's a good chance its hardware simply isn't capable of delivering the speed your ISP promises. For example:

• Routers with Wi-Fi 4 (802.11n) they physically can't distribute more 300–450 Mbps (even if the provider gives 1 Gbps).
• Models with a single-core processor (eg. TP-Link TL-WR841N) slow down when 10+ devices are connected simultaneously.
• Routers without MU-MIMO They can't communicate with multiple devices at the same time—they have to "switch" between them, which reduces speed.

How to tell if your router is outdated:

• The maximum speed via Wi-Fi is lower than via cable, even when standing next to the router.
• The router gets very hot or freezes periodically.
• There are no options in the settings Wi-Fi 5/6, MU-MIMO or Beamforming.

If the problem is in the hardware, there are two options:

1. Buy a new router with support Wi-Fi 6, MU-MIMO and multithreading (for example, Asus RT-AX88U or Netgear Nighthawk RAX50).
2. Use a router as an access point, connecting it to a more powerful main router via cable.

⚠️ Attention: cheap routers for 1000-1500 rubles (for example, D-Link DIR-615 or Tenda FH1201) often have weak antennas and processors. They're suitable for small apartments with 2-3 devices, but won't handle the workload of a modern home. Investing in a mid-range router (TP-Link Archer AX20, Keenetic Extra) will pay for themselves through stable operation.

6. Incorrect Router Placement: How Walls and Distance Steal Signal

Even the most powerful router is useless if it's in the wrong location. Wi-Fi signals weaken when passing through obstacles, and some materials (such as concrete or metal) block them almost completely.

Common placement mistakes:

• 🚪 The router is in the hallway or behind a closed door.
• 🪑 Hidden in a closet or behind the TV.
• 🌊 Near an aquarium (water strongly absorbs the signal).
• 🔌 Connected via an extension cord (unstable power supply will impair performance).
• 📡 Antennas are directed towards the wall or ceiling.

Optimal location:

1. Install a router in the center of the house (or closer to the place where you most often use the Internet).
2. Lift it up to a height of 1–2 meters (for example, on a shelf or table).
3. Point the antennas perpendicular to each other (one vertical, one horizontal) for better coverage.
4. Make sure there is no one nearby metal objects (refrigerator, radiator, mirror).

If the signal is still weak in some rooms, consider:

• 🔄 Wi-Fi repeater (signal amplifier, for example, TP-Link RE605X).
• 🔗 Powerline adapters (Internet transmission via electrical wiring, Devolo Magic 2).
• 📶 Mesh system (multiple access points operating as one network).

7. External factors: viruses, VPNs, and provider restrictions

Sometimes the problem isn't with the router, but with external factors. Here's what to check:

7.1 Viruses and malware

Some viruses use your internet connection to send spam, mine cryptocurrency, or launch DDoS attacks. This can consume up to 80% of your bandwidth. Signs:

• High network traffic even when you are not using the Internet.
• Advertising in the browser, redirects to strange sites.
• Unknown processes in Task Manager (Windows) or Activity Monitor (macOS).

Check all devices with an antivirus (for example, Kaspersky Internet Security or Malwarebytes).

7.2. VPN and proxy

If you use a VPN (eg. NordVPN, ProtonVPN), it can artificially limit the speed due to:

• VPN server overload.
• Traffic encryption (adds overhead).
• Geographical distance of the server.

Disable your VPN and test your speed without it. If it improves, try changing servers or your VPN provider.

7.3. Provider restrictions

Providers sometimes limit speed for the following reasons:

• 📉 Traffic limit exceeded (relevant for tariffs with “unlimited” Internet up to a certain volume).
• 🕒 Peak hours (In the evening, when everyone is watching Netflix, the speed may drop).
• 🔒 Throttling (artificial speed limitation for certain services, such as torrents).
• 📡 Problems on the line (damaged cable, faults at the station).

How to check:

1. Call your provider's support team and ask about current restrictions.
2. Check your speed on your provider's website (sometimes the actual rate is displayed there).
3. Connect to the internet via a mobile network (4G/5G) - if the speed is normal there, the problem is on the provider's side.

⚠️ AttentionSome providers (especially mobile operators) list speeds of "up to 100 Mbps" in their plans, but actually offer 10–20 Mbps. This isn't a scam—the "up to" phrasing allows for speed limitation. Check with them. guaranteed speed in the contract.

8. Additional settings for advanced users

If all the previous steps didn't help, try these advanced tricks:

8.1 Changing MTU

MTU (Maximum Transmission Unit) — the maximum data packet size. If it's too large, packets are truncated, slowing down the connection. The optimal value for most networks is 1472 or 1500.

How to change:

In Windows:
netsh interface ipv4 set subinterface "Connection_Name" mtu=1472 store=persistent

On the router: find the setting MTU in the section WAN or Internet.

8.2. Disabling WMM (Wi-Fi Multimedia)

WMM — a technology that prioritizes traffic for multimedia (e.g., video or voice calls). Sometimes it conflicts with some devices and slows down the network. Try disabling it in your router settings (Wireless Settings → WMM).

8.3. DNS settings

If websites load slowly, but the speed tests show it's normal, the problem may be DNS servers provider. Try using public DNS:

• 8.8.8.8 And 8.8.4.4 (Google DNS).
• 1.1.1.1 And 1.0.0.1 (Cloudflare DNS).

How to change: in the router settings, find the section DNS or Internet and enter new addresses.

8.4 Enabling Beamforming

Beamforming — a technology that focuses the Wi-Fi signal toward the connected device rather than dispersing it in all directions. Enable it in your router settings (Wireless Settings → Beamforming or Explicit Beamforming).

What to do if nothing helps?

If after all these steps the Wi-Fi speed is still low, try:

1. Reset the router to factory settings (button Reset on the back panel).

2. Connect another device to the router. If the speed is normal on it, the problem is with the first device.

3. Test the router on a different internet connection (for example, at a friend’s place or via a mobile USB modem).

If this doesn’t help, the router is faulty and requires repair or replacement.

FAQ: Answers to Frequently Asked Questions

Why is the speed via Wi-Fi lower than via cable – is this normal?

Yes, this is normal. Data is transmitted almost losslessly over a cable, while Wi-Fi is subject to interference, standard limitations, and distance. Under ideal conditions, the drop is 10–20%; in reality, it can be up to 50%. If the difference is greater, look for a problem in your settings or hardware.

What Wi-Fi standard is needed for 1 Gbps speed?

For speed 1 Gbps and above is needed Wi-Fi 5 (802.11ac) with channel width 80 MHz or Wi-Fi 6 (802.11ax)Please note: even if your router supports these speeds, your device (laptop, smartphone) must also be compatible. For example, iPhone 11 supports Wi-Fi 6, A iPhone 8 - only Wi-Fi 4.

Can a microwave really interfere with Wi-Fi?

Yes, and very much so. Microwave ovens operate at a frequency 2.4 GHz, like many routers. When heating food, they create powerful interference that can completely cut off Wi-Fi for several minutes. Solution: switch the router to 5 GHz or use it while the microwave is running.

Should I disable the old 802.11b standard to speed up my network?

Yes, as long as you don't have devices older than 10-15 years. Standard 802.11b limits the speed of the entire network to 11 Mbps, even if modern devices are connected. In the router settings, select the mode 802.11g/n (For 2.4 GHz) or 802.11n/ac/ax (For 5 GHz).

Do AliExpress signal boosters help?

Most cheap signal boosters (for example, those priced at 200–500 rubles) not only don't help, but actually make the situation worse. They create additional interference and can reduce speed. If you need a repeater, choose models from trusted brands: TP-Link, Netgear, AsusThe best option is Mesh systems, which automatically select the best channel.