title: "How to Tell If Someone Is Stealing Your Wi-Fi (And What to Do About It)" description: "Wi-Fi suddenly slow and you don't know why? Here's how to check who's actually on your network and lock it down if someone shouldn't be there." date: "2026-09-01" keywords: ["is someone stealing my wifi", "how to check who is on my wifi", "unknown device on wifi", "wifi security check", "change wifi password", "guest network setup", "wifi slow unknown device"]
Your Wi-Fi has been crawling for a week and you've already restarted the router twice. You start wondering if the problem isn't your internet plan at all, but someone else on your network you don't know about. Here's how to actually check, and what to do if you find someone there.
Check how many devices are actually connected
Open your router's app or log into its admin page (usually 192.168.0.1 or 192.168.1.1 typed into a browser). Look for "Connected Devices" or "Client List." Count what's there against what you actually own: phones, laptops, smart TVs, thermostats, doorbell cameras, game consoles, tablets. If the number connected is higher than the number of devices your household owns, something else is on your network.
Most router apps, including eero, Google Wifi, and Netgear Orbi, show device names automatically. A device labeled "Unknown" or a name that doesn't match anything you bought is your first real clue.
Watch for the signs before you even open the app
A stranger on your network usually shows up as a pattern, not one dramatic event. Wi-Fi that was fine for months suddenly drags at the same time every evening. Your router's activity light blinks heavily even when every device in the house is asleep. None of these prove someone stole your password, but together they're worth checking.
Rule out the boring explanation first
Before assuming a stranger, rule out your own house. Smart plugs, robot vacuums, and old phones sitting in a drawer still connected to Wi-Fi all show up as separate devices and all pull bandwidth. A lot of "mystery devices" turn out to be a kid's old iPad or a smart bulb nobody remembers installing.
If someone really is on your network
The fix isn't complicated. Change your Wi-Fi password from the router app, using a long passphrase instead of a short word-and-number combo. Every device you own needs the new password re-entered, which is the point: whoever was connected gets kicked off and can't get back in.
While you're in there, turn off WPS if it's enabled. WPS lets devices connect with a button press instead of a password, and it's a known weak point older routers still leave on by default.
Set up a guest network for visitors
If people regularly connect to your Wi-Fi, house guests, a kid's friends, a contractor, give them a separate guest network instead of your main password. Guest networks keep visitor devices off your main network entirely, so even if that password gets shared around, your actual devices stay protected.
When it's worth calling someone
If you've checked the device list, changed the password, and disabled WPS, and your Wi-Fi is still slow or a device keeps reappearing after you kick it off, that points to something bigger: a router that's been compromised, outdated firmware with a known vulnerability, or a router that's simply too old to lock down properly.
That's the point where guessing costs you more time than it saves. A SageTech tech can check your router's actual security settings, update the firmware, and lock the network down properly in one visit, so you're not repeating this every few months.
Frequently Asked Questions
How do I know if someone is stealing my Wi-Fi?
Check your router's connected devices list against what your household actually owns. An unfamiliar device name, combined with sudden slow speeds, is the clearest sign.
Will changing my Wi-Fi password remove someone who's already connected?
Yes. Changing the password disconnects every device, including any unauthorized one, and requires the new password to reconnect.
What is WPS and should I turn it off?
WPS lets devices join your network with a button press instead of a password. It's convenient but a known security weak point. Turning it off closes that entry point.
Does a guest network actually protect my main devices?
Yes. A guest network keeps visitor devices isolated from your main network, so a shared guest password never exposes your personal devices or files.
Download SageTech and book a visit if your Wi-Fi still feels off after locking things down.
Need help with this?
Book a SageTech tech to come to your home.