Maintenance procedure · Written to ASD-STE100 Issue 9 · Formatted to ANSI Z535

Slow WiFi at Home: Find Out Which Part Is Actually at Fault

A measure-first diagnostic for a home WiFi network that is slow or keeps dropping — separates the device, the WiFi, the router and the internet service before you change anything
ApplicabilityA home wifi network with a modem and a router, or a single combined modem-router from an internet provider. The measuring steps work from any device. The Windows steps were checked against Microsoft's documentation for Windows 11 and Windows 10 on 2026-07-29. The channel numbers given are the United States numbers.
Task time1 hr 24 min to 2 hr 4 min editorial estimate, not a measurement
PersonnelOne
Revisionv1 · 2026-07-29
BEFORE YOU BEGIN

Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.

Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.

Summary

Slow wifi is four different faults wearing the same costume. The problem can be in one device, in the radio link between that device and the router, in the router or modem, or upstream in the internet service you are paying for. They feel identical from the sofa, and every one of them has a different fix — which is why the single most common mistake is to start changing router settings before knowing which of the four you have.

This page does not change your network. It measures it. You take a speed reading in each room, repeat it on a second device, repeat it through a cable if you have one, restart the modem and router in the order Microsoft documents, and then work through the radio conditions and the Windows settings. At the end you have a sheet of numbers that either tells you the answer or gives your internet provider something better than "the wifi is bad". Where Apple and Microsoft disagree — and on two settings they flatly do — this page names both and sends you to your router's own documentation instead of picking a winner.

Safety

NOTICE

MEASURE THE NETWORK BEFORE YOU CHANGE THE NETWORK.
A change with no initial measurement gives you no comparison. You cannot then tell an improvement from a coincidence.

Necessary equipment

ItemNote
A phone, tablet or laptop with wifiUse the same device for each speed test. A different device gives a different result.
A second device with wifiThe second device shows if the fault is in one device or in the network.
A speed test app or websiteUse the same speed test for each measurement.
Pen and paperWrite each result with the name of the room and the time.
Network cable optionalOptional. A cable test separates the wifi from the internet service.

Measure the network first

Estimated 21 min to 32 min

NOTEMicrosoft tells you to make a baseline before you make a change to the network. Without a baseline, no later measurement has a comparison.
Speed your internet service is meant to give you
Unverified — do not rely on this value
CONSULT YOUR INTERNET SERVICE PROVIDER

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

  1. Write the day and the time of each slow period for one week.
    • A fault at the same time each evening is a different fault from a fault at all hours.
    5mReport a problem with step 1, Measure the network first
  2. Find the speed that your internet service gives you.
    • The monthly bill or the account page of the provider shows this speed.
    • Write this speed at the top of your sheet.
    3mReport a problem with step 2, Measure the network first
  3. Do a speed test on your device in the same room as the router.
    • Stay some metres away from the router.
    • Microsoft says that the strongest signal is a short distance from the router, not against it.
    2mReport a problem with step 3, Measure the network first
  4. Write the result with the name of the room and the time.
    <1mReport a problem with step 4, Measure the network first
  5. Do the same speed test in each other room of the home.
    • Use the same device and the same speed test each time.
    • Include the rooms where the network is good.
    8mReport a problem with step 5, Measure the network first
  6. Write each result with the name of the room and the time.
    • This sheet is the baseline. Keep it.
    2mReport a problem with step 6, Measure the network first

Find the part that is at fault

Estimated 11 min to 15 min

  1. Do the same speed test on a second device in the same room.
    • Microsoft tells you to try the same network from another laptop or phone.
    • A slow result on both devices points to the network.
    • A slow result on only one device points to that device.
    3mReport a problem with step 1, Find the part that is at fault
  2. Write the second result on the same sheet.
    <1mReport a problem with step 2, Find the part that is at fault
  3. If a computer has a socket for a network cable, connect it to the router with the cable.
    • This is the one test that removes the radio from the measurement.
    • If no device has such a socket, go to the next section.
    4mReport a problem with step 3, Find the part that is at fault
  4. Do the same speed test through the cable.
    • A good result through the cable points to the wifi part of the network.
    • A slow result through the cable points to the modem or to the internet service.
    2mReport a problem with step 4, Find the part that is at fault
  5. Write the cable result on the same sheet.
    <1mReport a problem with step 5, Find the part that is at fault
  6. Disconnect the cable.
    <1mReport a problem with step 6, Find the part that is at fault

Do a restart of the modem and the router

Estimated 12 min to 18 min

NOTEThe order is important. The modem must be ready before the router starts.
NOTICE

TELL THE OTHER PERSONS IN THE HOME BEFORE YOU START THIS SECTION.
The restart stops the network for every device in the home for some minutes.

  1. Disconnect the power cable of the router from the wall socket.
    • A combined modem-router is one device. For that device, do only the router steps.
    <1mReport a problem with step 1, Do a restart of the modem and the router
  2. Disconnect the power cable of the modem from the wall socket.
    • Some modems contain a battery.
    • If the lights stay on, remove that battery.
    1mReport a problem with step 2, Do a restart of the modem and the router
  3. Wait a minimum of 30 seconds.
    <1mReport a problem with step 3, Do a restart of the modem and the router
  4. If you removed a battery from the modem, install that battery again.
    <1mReport a problem with step 4, Do a restart of the modem and the router
  5. Connect the power cable of the modem to the wall socket.
    <1mReport a problem with step 5, Do a restart of the modem and the router
  6. Wait until the lights on the modem are steady.
    • The lights blink while the modem starts.
    3mReport a problem with step 6, Do a restart of the modem and the router
  7. Connect the power cable of the router to the wall socket.
    <1mReport a problem with step 7, Do a restart of the modem and the router
  8. Wait some minutes until the modem and the router are fully on.
    • The status lights on the two devices show this condition.
    4mReport a problem with step 8, Do a restart of the modem and the router
  9. Do the speed test again in the same room. Write the result.
    2mReport a problem with step 9, Do a restart of the modem and the router

Do a check of the radio conditions

Estimated 14 min

NOTEA 2.4 GHz signal goes through walls better than a 5 GHz signal. A 5 GHz signal is faster and has a shorter range.
Network name for a router with more than one band
Unverified — do not rely on this value
CONSULT THE DOCUMENTATION FOR YOUR ROUTER. TWO MANUFACTURERS GIVE OPPOSITE INSTRUCTIONS.

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

Apple and Microsoft disagree, and this page publishes the disagreement instead of choosing. Apple, in 'Recommended settings for Wi-Fi routers and access points' (published 14 July 2026), says to set a single, unique network name for all bands, and warns that different names per band can stop devices connecting reliably. Microsoft, in 'Wi-Fi and your home layout', says the opposite: if your router broadcasts on 2.4 GHz, 5 GHz and 6 GHz you should use different network names so you know which one you are on. Both are first-party manufacturer documentation and both were read on 2026-07-29. Neither is averaged and neither is preferred here. Note that the isolation step on this page works either way: with one name you cannot choose a band by hand, and with two names you can.
Method to choose the wifi channel
Unverified — do not rely on this value
CONSULT THE DOCUMENTATION FOR YOUR ROUTER. TWO MANUFACTURERS GIVE DIFFERENT INSTRUCTIONS.

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

Apple and Microsoft disagree. Apple's 'Recommended settings for Wi-Fi routers and access points' says to set channel selection to Auto, because the router then selects the best channel for you. Microsoft's 'Wi-Fi and your home layout' says that some routers do this well and others do not, and that you should pick the best channel for your home yourself. TP-Link's own support page sits between them: it says the default value is Auto and that you should consider a fixed channel only if you have high interference. Both readings were taken on 2026-07-29. This page does not reconcile them and does not instruct a channel change; it routes you to your router's documentation.
Wifi channels that do not overlap on the 2.4 GHz band in the United States
Manufacturer or standard verified
1, 6 or 11 channel number

Source: Wi-Fi and your home layout · tier 1 · accessed 2026-07-29

Channel width to use on the 2.4 GHz band
Manufacturer or standard verified
20 MHz

Source: Recommended settings for Wi-Fi routers and access points · tier 1 · accessed 2026-07-29

Wifi security setting
Manufacturer or standard verified
WPA3 PERSONAL, OR WPA2 AND WPA3 TRANSITIONAL FOR OLDER DEVICES

Source: Recommended settings for Wi-Fi routers and access points · tier 1 · accessed 2026-07-29

NOTICE

FIND THE WI-FI PASSWORD BEFORE YOU CONNECT TO A DIFFERENT NETWORK NAME.
The second name can ask for the password again.

  1. Examine the list of wifi networks on your device.
    • Some routers show the two bands as two different network names.
    • Other routers show one name for both bands.
    1mReport a problem with step 1, Do a check of the radio conditions
  2. If the list shows two names for your router, connect to the other name.
    • Microsoft says that these two names appear as separate networks.
    • If the list shows one name, go to the next step.
    2mReport a problem with step 2, Do a check of the radio conditions
  3. Do the speed test again. Write the result and the network name.
    2mReport a problem with step 3, Do a check of the radio conditions
  4. Move the device nearer to the router.
    • Apple gives this action as the first remedy for interference.
    1mReport a problem with step 4, Do a check of the radio conditions
  5. Do the speed test again in the new position. Write the result.
    • A much better result in the new position points to distance or to an obstruction.
    2mReport a problem with step 5, Do a check of the radio conditions
  6. Make a list of the objects between the router and the slow room.
    • Apple puts metal at the top of its list of obstructions.
    • Plaster, concrete and bulletproof glass come next.
    • Water, bricks and marble have a medium effect.
    • Wood, glass and many synthetic materials have a low effect.
    3mReport a problem with step 6, Do a check of the radio conditions
  7. Set the electrical devices near the router to off for 10 minutes.
    • Apple names a power cable, a microwave oven and a fluorescent light as sources of interference.
    • Apple also names a wireless video camera and a cordless phone.
    • TP-Link adds a monitor, an electric motor and a fax machine.
    2mReport a problem with step 7, Do a check of the radio conditions
  8. Do the speed test again. Write the result.
    • A better result here points to one of those devices.
    2mReport a problem with step 8, Do a check of the radio conditions

Do a check of the Windows PC

Estimated 7 min to 11 min

  1. On a Windows PC, open the Settings app.
    • If you have no Windows PC, go to the next section.
    <1mReport a problem with step 1, Do a check of the Windows PC
  2. Open the network troubleshooter.
    • On Windows 11, Microsoft gives the Network and Internet troubleshooter in the Get Help app.
    • On Windows 10, select Network and Internet, then Status, then Network troubleshooter.
    2mReport a problem with step 2, Do a check of the Windows PC
  3. Obey the instructions on the screen.
    • The troubleshooter can make a change without a question to you.
    3mReport a problem with step 3, Do a check of the Windows PC
  4. Type device manager in the search box on the taskbar.
    <1mReport a problem with step 4, Do a check of the Windows PC
  5. Select Device Manager in the results.
    <1mReport a problem with step 5, Do a check of the Windows PC
  6. Find your wifi adapter in the group of network adapters.
    • Right-click the adapter.
    • Select Properties.
    • Select the Power Management tab.
    1mReport a problem with step 6, Do a check of the Windows PC
  7. Clear the check box in the Power Management tab.
    • Microsoft names this check box "Allow the computer to turn off this device to save power".
    • Windows then does not decrease the power to the adapter.
    <1mReport a problem with step 7, Do a check of the Windows PC

Find the boundary of your network

Estimated 19 min to 34 min

Router firmware version
Unverified — do not rely on this value
CONSULT THE MANUFACTURER OF THE ROUTER

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

NOTICE

TYPE ONLY THE TWO COMMANDS ON THIS PAGE.
A different command at this prompt can change the network settings of the PC.

  1. Type command prompt in the search box on the taskbar.
    • Select Run as administrator at the Command Prompt result.
    • Select Yes.
    <1mReport a problem with step 1, Find the boundary of your network
  2. Type ipconfig at the prompt. Push Enter.
    <1mReport a problem with step 2, Find the boundary of your network
  3. Read the address at the Default Gateway line for your wifi network.
    • Write this address. It is the address of your router.
    • Microsoft gives 192.168.1.1 as an example of such an address.
    1mReport a problem with step 3, Find the boundary of your network
  4. Type ping and that address at the prompt. Push Enter.
    <1mReport a problem with step 4, Find the boundary of your network
  5. Read the result of the ping test.
    • A reply from the address shows a good connection to the router.
    • Microsoft says that a good reply points to the modem or to the internet service.
    • No reply points to the connection between the PC and the router.
    1mReport a problem with step 5, Find the boundary of your network
  6. Put all the results on one sheet.
    • Show the speed of the internet service at the top.
    • Show each speed test with its room, its time and its network name.
    • Show the cable result and the ping result.
    5mReport a problem with step 6, Find the boundary of your network
  7. If the cable result is also slow, speak to your internet service provider.
    • Give the provider the sheet.
    • Ask the provider for a check of the line and for a report of a local service fault.
    10mReport a problem with step 7, Find the boundary of your network

Terminology

This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.

router
Also called: wifi box, the wifi, wireless router, internet box, hub, the black box with the lights
modem
Also called: cable box, broadband box, the box from the internet company, ONT, gateway
band
Also called: frequency, 2.4 or 5, the fast wifi, the long range wifi, 5G wifi, 5 gig wifi
network name
Also called: SSID, wifi name, the name of my wifi, network ID
internet service provider
Also called: ISP, the internet company, broadband provider, cable company
wifi adapter
Also called: wireless card, wifi card, network adapter, wireless adapter, wifi chip
default gateway
Also called: router address, router IP, 192.168.1.1, the address you type to get into the router

When to use a professional

Stop at the router configuration page. This page measures your network. It does not change router settings, because the menus, the names and the effects are different for each model. Apple says to use the configuration webpage or app from the router manufacturer and to consult that manufacturer for details. Do the same.

Stop if the cable result is as slow as the wifi result. That result points away from your wifi and towards the modem or the line. Speak to your internet service provider. Give them the sheet of measurements.

Stop if an employer or a school controls the PC. A policy on a controlled PC can hold the network settings. Speak to your IT administrator.

Stop if the router is the property of your internet service provider. Ask the provider to do a check of it. A change you make to provider equipment can end its support.

Common questions

Why is my wifi slow at night but fine in the morning?

That pattern is the reason step one asks you to write down times for a week before you touch anything. A fault that appears every evening and clears by morning is usually contention rather than a broken network: more of your own devices are streaming, and more of your neighbours' networks are busy on the same channels. A fault that is present at all hours is more likely to be placement, an obstruction, or the service itself. The two have completely different fixes, and a week of dated notes tells them apart for free. Nothing else on this page can.

Should I use the 2.4 GHz or the 5 GHz network?

Neither is better; they trade range against speed. Microsoft's own comparison gives 2.4 GHz longer range, better behaviour through walls and wider device compatibility, but slower throughput, fewer non-overlapping channels and more congestion — partly because microwaves, cordless phones and Bluetooth all share that band. It gives 5 GHz faster throughput, more non-overlapping channels and less congestion, but shorter range and worse penetration through walls. TP-Link says the same thing about 5 GHz being more sensitive to obstacles. In practice: 5 GHz in the same room as the router, 2.4 GHz at the far end of the house. That is exactly what the room-by-room speed test is measuring for you.

Should my 2.4 GHz and 5 GHz networks have the same name or different names?

This is the one question on this page where two tier-one manufacturers flatly contradict each other, so we publish the contradiction rather than pick a side. Apple says to set a single, unique name for all bands and warns that different names per band can stop devices connecting reliably to all of them. Microsoft says you should use different names precisely so you know which band you are on. Both were read on 29 July 2026 and both are first-party documentation. Your router's own manual is the tiebreak. Practically, note that separate names give you the manual band test in this page's radio section, and a single name does not — which is a reason to have them separated while you are diagnosing, whatever you settle on afterwards.

Is a wifi extender or a mesh system the answer?

Possibly, but not until you know which of the four faults you have, and an extender fixes exactly one of them. If your cable test is as slow as your wifi, the problem is upstream and an extender will faithfully extend a slow connection to more rooms. If one device is slow and the rest are fine, the problem is that device. An extender helps when the numbers show good speed near the router and poor speed at distance, with obstructions in between — which is what the room-by-room sheet shows at a glance. Microsoft and TP-Link both list extenders and additional access points under coverage, not under speed.

Do I really need to restart the modem and the router in that order?

Follow it, yes. Microsoft's article gives the order explicitly: unplug both, wait at least 30 seconds, plug the modem back in and wait for its lights to stop blinking, and only then plug the router back in. The reason is that the router asks the modem for its address when it starts; if the modem is not ready yet, the router can come up without a working connection and you will restart it a second time anyway. If you have a single combined modem-router from your provider, there is only one device and only one power cable to pull.

The speed test says I'm getting the speed I pay for, but everything still feels slow. What now?

Then the number you need is not throughput. A connection can hit its rated download speed and still feel bad because of latency or packet loss, which is what the ping test at the end of this page starts to show. Run it while the network feels slow, not afterwards. Microsoft's article uses that same test to draw the boundary: replies from your router mean the link to the router is fine and the problem is beyond it, and no reply means the problem is between the PC and the router. Take both numbers to your provider — a speed figure alone invites the answer that your line tests fine.

Why does this page not tell me to reset my network settings?

Because network reset is a repair for a connection that does not work, not for one that is slow, and it costs you every saved wifi network and password on the machine. Microsoft is explicit that it should be the last step you try, and it notes you may then have to reinstall VPN client software and reconfigure virtual switches. None of that helps a page whose whole job is measuring. If you finish this page, find the fault is in one Windows PC, and nothing in the Windows section moved it, network reset is a reasonable next thing to read about in Microsoft's own article — which is linked in the sources.

Sources

Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.

  1. Tier 1Fix Wi-Fi connection issues in WindowsMicrosoft · accessed 2026-07-29 · re-verification due 2027-01-25
  2. Tier 1Wi-Fi and your home layoutMicrosoft · accessed 2026-07-29 · re-verification due 2027-01-25
  3. Tier 1Recommended settings for Wi-Fi routers and access pointsApple · accessed 2026-07-29 · re-verification due 2027-01-25
  4. Tier 1Resolve Wi-Fi and Bluetooth issues caused by wireless interferenceApple · accessed 2026-07-29 · re-verification due 2027-01-25
  5. Tier 1How to Improve Your Wi-Fi Signal and Wireless RangeTP-Link · accessed 2026-07-29 · re-verification due 2027-01-25
  6. Tier 1TP-Link Router Antenna Position and Placement Guide: 6 Tips for Better Wi-FiTP-Link · accessed 2026-07-29 · re-verification due 2027-01-25

Revision history

Current version 1 · updated 2026-07-29 · next review due 2027-07-29

  1. v1 · 2026-07-29First draft. Built from six tier-1 manufacturer documents read in full on 2026-07-29: Microsoft's 'Fix Wi-Fi connection issues in Windows' and 'Wi-Fi and your home layout', Apple's 'Recommended settings for Wi-Fi routers and access points' (published 14 July 2026) and 'Resolve Wi-Fi and Bluetooth issues caused by wireless interference' (published 23 April 2025), and TP-Link's support pages 468 (last updated 17 April 2026) and 455 (last updated 26 May 2026). Written as doc_type diagnostic rather than procedure: the page measures and isolates, it does not reconfigure, and its professional boundary at the router configuration page is the point of it. TWO GENUINE SOURCE CONFLICTS ARE PUBLISHED RATHER THAN RECONCILED, both between Apple and Microsoft: whether the bands of a multi-band router should share one network name or have separate ones, and whether the wifi channel should be left on Auto or chosen by hand. Both are recorded in specifications with conflict_note and both are named in the FAQ. NOT PUBLISHED, deliberately: any signal strength figure in dBm, because the sentence in Microsoft's article that would supply it cannot be read unambiguously as printed; any household broadband speed recommendation, because the FCC pages that carry it returned HTTP 403 to every request and were never read; and any router setting change, because the menus differ by model and Apple's own documentation sends the reader to the router manufacturer. Verified specifications carry no spec_key: data/specs.json could not be written in this session because several agents were drafting at once, so the four verified values here must be registered centrally at merge time. Sources are staged in data/sources-additions-diagnose-slow-wifi.json, which also records eleven rejected URLs including three FCC pages that returned 403, a NETGEAR knowledge-base article that returns HTTP 200 with a JavaScript redirect to an error page, and two Microsoft Q&A threads that are tier 3 by kind on a tier-1 host.

Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.

Comments and corrections

Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.

Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.

The comment system is not connected yet. Comments are stored in GitHub Discussions through Giscus, outside this site, so that a redeploy cannot destroy them.