Router WiFi disconnects from time to time, and the internet speed is getting slower and slower?

WiFi at home disconnects when used, or the internet speed is getting slower and slower, watching video cards, playing games, and pinging? Don't rush to change the router, check it in order first.

today we will arrange the common causes according to investigation priority starting from the most problematic link and going all the way to the bottom.

Problem Diagnosis: What are the common causes of WiFi disconnection and slow internet speed?

start with the fact that most WiFi issues are temporary interference or minor issues with the router itself, can be fixed without changing the device.

Common causes (sorted by frequency):

router WiFi channel congestion - Neighbors are all using the same channel, and the signal interference is severe
router runs for a long time and heats up badly performance degrades after a few weeks of continuous power-up
devices are too far away or there are too many partitions - the signal itself is weak and the speed is naturally low
operator bandwidth itself is not enough - it is also a waste to run a gigabit router with 100 gigabit broadband
Terminal device network card problem - Wireless network card failure of mobile phone/computer
router firmware has Bug – outdated firmware causes abnormal interruptions

Solution

Solution 1: Restart the router (90% of problems will be solved)

the easiest way and the most effective.

Steps:

unplug the router power cord
wait 30 seconds for (let the capacitor discharge completely)
plug it back in
wait 2-3 minutes for the light to stabilize before connecting WiFi

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Tip: Set your router to automatically restart once a week (most routers support scheduled restarts) to prevent 90% of nighttime disconnection problems.

suitable for people: lazy, in a hurry, temporary breakdowns.

Option 2: Replace WiFi Channels

channel congestion is the most common cause of chronic disconnection, especially in high-rise buildings.

How to check if the channel is congested?

Android phone: Download the "WiFi Analyzer" app to check the occupancy of each channel
iPhone: Search for "WiFi Scanner" in the App Store (some charges)
computer: Use the InSSIDer or WirelessMon tool

How did

convert to faith?

Enter the router background address
the browser (common: 192.168.1.1 / 192.168.0.1 / 192.168.31.1)
Login to the background (username and password are usually labeled on the back of the router)
find "Wireless Settings" or "WiFi Settings"
change the channel from "Auto" to: 2.4G band 1, choose one of the 1, 6, 11 (these three do not interfere with each other); 5G Frequency bands 149, 153, 157, 161 (commonly used in China)
save and restart your router

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Avoid pitfalls:

do not choose the automatic channel - the router will not switch intelligently, it should be fixed manually
2. Do not select 12 or 13 in the 4G band channel (some devices are not compatible)
5G It is normal to pass through walls, don't force it to pass through more than two walls

Suitable for: high-rise residents, densely populated areas of the city, and environments with a lot of WiFi in the surrounding area.

Scenario 3: Adjust WiFi bandwidth to reduce interference

many routers maximize bandwidth by default (40MHz/80MHz), but the larger the bandwidth, the easier it is to interfere.

Change Method:

2.4G band: Reduces bandwidth from 40MHz to 20MHz
→ with a slight reduction in speed, but greatly improves stability
5G band: Maintain 80MHz (when the need to pass through the wall is not high)

suitable for the scene:

2.4G WiFi is mainly for smart homes (cameras, speakers) and does not require high speed
5G WiFi for mobile phones and computers, it can run full bandwidth

Scenario 4: Check if the router is heating

router will heat up after running for a long time, which can lead to downscaling and interruption, and crashing at worst.

Judgment Method:

touch the router shell, hot hands (over 50°C) indicate a heat dissipation problem
more likely to occur in summer

Solution:

place the router in a well-ventilated location and do not stuff it into a weak current box
use a few books to raise the bottom of the router to increase the cooling space
summer, you can consider adding a small fan to blow

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pit avoidance:

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Do not cover the router with towels or newspapers
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Don't put your router in a corner, in a cabinet – it dissipates heat very poorly
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Don't stack your router and light cat on top of each other – heat stacks

Suitable for: Users whose routers are placed in confined spaces and whose devices heat up severely.

Solution 5: Troubleshoot the terminal device

if only one device is disconnected and the others are fine – the problem is on the device side, not the router.

Phone/Tablet:

Forgot WiFi Reconnect: Set up → WiFi → Tap Network → Ignore this network → Re-enter the password connection
restart your phone (many people forget such a simple step)
Update system firmware (iOS/Android)

PC (Windows):

open Device Manager → Network Adapter → find the wireless adapter → update driver
Run Network Reset: Set up → Network and Internet → Network Reset

Computer (Mac):

System Preferences → Network → Select WiFi → Click on "Advanced" → Remove the preferred network → Add it again
reset SMC (Network Hardware Reset for Intel Macs)

Scenario 6: Test the bandwidth and check with the operator to confirm the

run a speed test to rule out external factors.

Open your browser to access the speedtest.net
use a network cable to connect directly to the router for speed measurement (WiFi speed test results are inaccurate)
Compare the contracted bandwidth: 100M broadband theoretical download speed 12.5MB/s

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pit avoidance:

WiFi Speed is always 30-50% slower than wired, which is normal, don't blame the router
evening peak (20:00-23:00) bandwidth will already drop, which is caused by operators sharing bandwidth

final reminder

reboot, then change channels, and finally suspect hardware —this sequence solves 90% of the problems
2.4G and 5G have separate SSIDs to determine which frequency band is problematic
the router is placed high in the middle of the house, do not put a weak electrical box or on the ground
check for firmware updates regularly (semi-annually) and the vendor fixes known Bug

the fastest solution is to restart, the most stable solution is to change the channel, and the most thorough solution is to change the router position.

What other network problems

have? Tell me in the comment area.