WiFi Scan

Find Out Who on my WiFi to Prevent Unauthorized Access

How to Check Who is on my WiFi

Perhaps the most problematic aspect of WiFi networks is the security exposure that they can present. It is much easier to conduct an attack on a WiFi network than on a wired installation. If an unauthorized user accesses or is using your network, they will be harder to detect than individuals attacking a more traditional network. This can definitely be a problem with either home or business users of WiFi networks.

Why Would Anyone Want to Connect to My WiFi Network?

This question has a number of potential answers, none of which are beneficial to the owner of the WiFi network in question. It’s in your best interest to know who is on your WiFi and what they are doing while they are connected. Unauthorized users may be accessing your network for a number of reasons. Among them are:

  • Subverting their own download limitations – Using your network to download their large files can greatly increase the amount of data a user can access without going over the limits of their data plan. Your neighbor might actually prefer your network over theirs for this very reason.
  • Attempting to infiltrate your computer systems – Some intrusions may be directed at compromising your computers and the information that they contain.
  • Obtaining WiFi for free – Nearby users who do not have their own WiFi network may be using yours rather than pay for their own implementation.

What Harm Can Come From Unauthorized Users?

You want to know who is connected to your WiFi and what they are doing there. There are several potentially negative consequences that you may experience by allowing unauthorized users to access your WiFi network. Some of them are:

Overloading your WiFi network

Having extra users eating up your WiFI bandwidth can lead to slower data transmission than you should be achieving. You are also prone to dropped connections if too many users are on your network. If your network is not secure you may be providing a free ride for your neighbors while your family’s ability to stream and download content is crippled.

Compromised data

If someone with malevolent intentions can gain access to your WiFi network, they can also attempt to capture data transmissions which can lead to compromised passwords and stolen information. Devices that are shared on your network are available to the intruder who can use them for nefarious reasons. That shared hard drive that your company uses for financial reports can easily fall into the wrong hands if your network security is breached.

Malware infection

An all too common result of unauthorized access to your WiFi network is for your uninvited visitor to leave a little package of malware behind. Malware comes in many flavors, none of which are pleasant. An infection of this sort can cause performance issues with your systems as well as potentially capturing personal and sensitive information from your machine.

Attacking smart home implementations

Access to your wireless network will allow unauthorized users to hack into any WiFi-connected smart home devices. This can potentially cause great harm by turning off home security devices and allowing intruders to physically enter your home.

How Can I See What Devices Are Connected to My Network?

Now that you are aware of the reasons that someone would want to access your WiFi network and the problems that can be caused by unauthorized users, you probably want to know how to see who is on your WiFi. Luckily there are ways for you find out if other devices or users are on your network.

In order to answer the question of who is on your network, you need to use a specialized WiFi network security tool. There are hardware implementations, but these are usually used by network security professionals and can be quite costly. Most users can gather the data they need on network intrusion with one of the many software applications that are available for whichever operating system or platform you are using.

Determining Who’s On My WiFi with KisMAC

KisMAC is a freeware, open-source WiFi security tool developed for use on Mac computers. It was originally intended to be used by security professionals, and for this reason, it is not the most user-friendly piece of software that you will ever use. It will, however, enable you to monitor your WiFI network. In some cases, you may need an additional USB network card in order to successfully scan your network with this tool.

After downloading and installing the tool, you will be able to scan for nearby WiFi networks and create a list of users who are currently logged in. Using this information you can easily determine if there is an unauthorized user or devices attached to your network.

Tools That Can Show You Who is Connected to Your WiFi

Here is a selection of other WiFi security tools that you can employ to find out who might be connecting to your network without an invitation.


Windows users can take advantage of the features of this firewall and security application. It can perform a variety of security functions, but for our purposes, the most appealing is the ability to set alerts when unknown devices connect to your WiFi network. A version for macOS users is in the works.


With the NetSpot WiFi analyzer application, you can monitor and troubleshoot the performance of your network. While the tool does not directly display devices attached to your network, it can help you understand the performance you should expect from it. If you find you are experiencing problems such as slower than usual speeds you may have unauthorized users accessing your network. The reports generated from the tool can help eliminate other sources of the problem from consideration and at that point, you can take preventative action.

Who’s On My WiFi

This software tool displays all devices that have accessed your network over a period of time. It runs on Windows and the Mac and by using the app you can easily detect if there are intruders accessing your network.

Wireless Network Watcher

Here is a small utility program that runs on all flavor of the Windows operating system. It allows you to see all devices that are connected to your WiFi so you can identify any unauthorized users.

Protecting Your WiFi Network

Taking proactive steps to protect your WiFi network is certainly preferable to tracking down unauthorized intruders. Your first line of defense is to secure your network by instituting encryption on your router. You should use WPA2 encryption at a minimum and include a strong password to restrict access to your network.

To successfully guard against brute-force attacks against your network, consider using a password that is at least twelve characters long. The length of time required to crack a password of this strength makes it extremely unlikely that your network will be compromised.

Failure to secure your WiFi network is as dangerous to your computing infrastructure as is leaving your front door open when you go to work. You can hope that nothing bad happens, but odds are they will. Take the necessary steps to ensure the safety of your data and the security of your WiFi network.