How do I detect unwanted or strangers connecting to our wifi?

If you have a sufficiently strong password, the slowdown is unlikely to be the fault of unauthorized connections. First, check what your other household members are doing. Streaming music and shows or playing online video games can lag other users on the same network. You can also try rebooting the router, especially if it has been in operation for a very long time. Switch it off, unplug it, count to ten, and start it up again. Finally, you can go to the Network and Sharing Center. There should be a simplified map of your network. Near that should be a link or button that will show the entire map of your local network. If you do find someone accessing your wifi without your permission, change your password immediately (and if you've used the same password anywhere else, change that, too.)

We don't have wifi at home. You may check the tech support and seek help from them.

From my experience, when someone intrudes the network, the network connection will slow down by a lot and there will be a lot of disconnections in and out. It's important to set your password for the connection and make sure that it's a very strong one.

Should notice a much slower internet speed, only way I know...

Oh and if everyone is using it from home I would suggest instead of just a password, use the physical code on your router as the access code. Everyone in your household can take a look at it easily and I think it's much safer than a normal password.

If anyone connect to your router their MAC address will get registered. You should be able to check that easily by connecting to your router and get the list of computers from it.

You can configure your router to connect with physical network id which is called mac id too.. so that you won't face such issue.. and yeah you can also check no of people connected with your router from it's console.. and other way you can frequently change your wifi password so that one cannot use it easily..

You can detect unwanted or strangers entering your wi-fi connection when your connection becomes slower. That is the most apparent reason that there are unwanted users of your network. To resolve it, go to the settings or properties of your network connection and make sure that you have to change your security information. Change your password so that no one can enter it.

Maybe check if your router detects people connecting to it. I know mine does. I just access my router using the usual 192.168.x.x (depending on which computer you access it from), and I think there's a part that shows me the MAC Address I think it was of everyone who's been connecting to it.

Im not sure exactly depending on your router, im sure you can find it on your manuel or online one. but you can make it where it accepts only your home computers and laptops mac addresses are only allowed as well as the password protect.

Try having another computer or laptop then try accessing your wi-fi connection. It is to try if the passwords work. Because as long as there is a password, anyone could see the connection for your wi-fi but they can never access it if they don't know the password. Try checking for your computer, it might be the problem, or maybe you go to places that the wi-fi isn't reached enough.

Thanks to you to initiate this discussion as well as to all who have answered with valuable information to increase security.