If your network is running slower than expected or you notice unfamiliar names in your router app, you may be dealing with unauthorized devices.
This guide explains how to remove unknown devices from WiFi, confirm whether they belong on your network, and lock down access before the problem returns.
Why Unknown Devices Appear on WiFi
Unknown devices usually show up for one of four reasons: a shared password, a guest who was never removed, a poorly secured router, or a device name that simply looks unfamiliar.
In some cases, a phone, smart TV, printer, or IoT device is labeled generically by the router, which makes it seem suspicious even when it is legitimate.
Before taking action, identify whether the device is actually unauthorized.
Router admin pages, mesh network apps, and ISP gateways often list the device type, MAC address, and connection time.
Compare those details with the devices in your home or office.
How to Identify the Device on Your Network
The fastest way to investigate is through your router’s connected devices page.
Look for the following information:
- Device name: Often a manufacturer label or a custom name assigned by the device owner.
- MAC address: A unique hardware identifier that helps distinguish one device from another.
- IP address: The local address the router assigned to the device.
- Connection band: Whether it is using 2.4 GHz, 5 GHz, or 6 GHz WiFi.
- Last active time: Helps you see whether the device is currently online or was connected earlier.
If the name is unclear, cross-check the MAC address against devices in your home.
On iPhone, Android, Windows, macOS, smart TVs, and gaming consoles, network settings often display a WiFi or hardware address.
This makes it easier to confirm whether the device is yours.
How to Remove Unknown Devices from WiFi
If you have confirmed the device is unauthorized, the most reliable way to remove unknown devices from WiFi is to block their access at the router and change the network credentials.
Simply disconnecting the device from a list may not stop it from reconnecting if the password remains the same.
1. Block the device in your router settings
Most modern routers and mesh systems include a device control page.
Find the connected device list, select the unfamiliar entry, and choose one of these options if available:
- Block
- Deny access
- Pause internet
- Blacklist device
This prevents the device from accessing your network, but it may still reconnect later if the WiFi password is not changed.
Blocking works best as a first step, not the final fix.
2. Change the WiFi password
Changing the WiFi password immediately disconnects every device from the network, including the unknown one.
After the reset, reconnect only trusted devices with the new password.
Use a strong passphrase with a mix of letters, numbers, and symbols.
Avoid personal details, reused passwords, and short combinations that can be guessed through brute-force attacks.
3. Rename the network if needed
If you suspect someone already knows your WiFi network name, consider changing the SSID as well.
A fresh network name makes it harder for previous guests or neighboring users to recognize and target your router.
4. Reboot the router after changes
After updating the password or security settings, restart the router to force all devices to reconnect under the new rules.
This is especially useful on older routers that do not immediately refresh access lists.
Best Router Settings to Use After Removal
Removing the device is only one part of the process.
Strong router settings help prevent repeat intrusions and reduce the chance of future compromises.
- Use WPA3 if supported: WPA3 offers stronger protection than WPA2 on compatible routers and devices.
- Use WPA2-AES if WPA3 is unavailable: Avoid outdated WEP or WPA modes.
- Disable WPS: WiFi Protected Setup can make it easier for attackers to gain access.
- Update router firmware: Firmware updates patch security vulnerabilities and improve stability.
- Set a new admin password: Protect the router login itself, not just the WiFi password.
Many attacks succeed because users change the WiFi password but leave the router admin account unchanged.
If an intruder can log in to the router, they may be able to re-add themselves or view sensitive network data.
How to Check for Hidden or Persistent Access
Some unauthorized users try to keep access by reusing saved credentials, exploiting weak admin settings, or connecting through a guest network.
Review every access path available on your router.
Guest network
If your router has a guest network, make sure it has a separate password and that old guest access is disabled.
Guest networks are useful for visitors, but they can become a backdoor if left unmanaged.
Saved devices and access control
Look for a device allowlist or parental controls section.
Some routers let you approve only specific devices by MAC address.
This is useful in homes with children, smart-home gear, or remote work devices.
Remote administration
Turn off remote router management unless you truly need it.
Leaving it on can expose the router interface to the internet, increasing the risk of compromise.
Signs Someone May Still Be on Your Network
Even after you remove unknown devices from WiFi, watch for warning signs that something is still wrong:
- Unexpected slowdowns during normal use
- New devices appearing after a password reset
- Router settings changing without your input
- Unknown DNS settings or browser redirects
- Frequent disconnections from trusted devices
These signs can indicate an unauthorized user, malware on a local device, or a compromised router.
If the problem persists after changing credentials, perform a factory reset on the router and reconfigure it from scratch.
When to Reset the Router Completely
A factory reset is the strongest option when you cannot identify the source of the problem or when the router appears compromised.
Resetting clears custom settings, saved passwords, port forwarding rules, and any unknown configuration changes.
After resetting, immediately:
- Set a new admin password
- Choose WPA3 or WPA2-AES security
- Create a strong WiFi password
- Disable WPS
- Reconnect only trusted devices
- Update router firmware
If the router was supplied by an internet service provider such as Comcast, Verizon, AT&T, Spectrum, or BT, you may also want to contact support for help checking account-level security settings.
How to Prevent Unknown Devices from Returning
Prevention depends on good habits and routine checks.
Review connected devices every few weeks, especially after guests visit or when you add new smart-home equipment.
- Use a unique WiFi password not used on other accounts
- Change the password after guests no longer need access
- Keep firmware updated on the router and mesh nodes
- Use separate networks for smart-home devices if possible
- Remove old or unused accounts tied to router apps
- Monitor alerts from your router or security app
For homes with many connected devices, network segmentation can reduce risk.
Placing IoT devices on a separate SSID or VLAN can limit damage if one device becomes compromised.
What to Do If You Suspect a Serious Security Issue
If you find repeated unauthorized access, unknown router logins, or signs of tampering, treat it as a security incident.
Change all credentials associated with the network, including the router admin password, WiFi password, and any ISP account password linked to the service.
Also scan trusted computers and phones for malware, because compromised endpoints can leak credentials back to an attacker.
If needed, ask your ISP or a qualified network technician to inspect the modem, router, and line provisioning.
Knowing how to remove unknown devices from WiFi is useful, but the deeper goal is to regain control of the network and keep it that way.
With the right router settings and routine checks, you can reduce unauthorized access and make your WiFi much harder to abuse.