This Raspberry Pi project reveals every device secretly tracking your family

Published Aug 27, 2026, 2:30 PM EDT Nick Lewis is an editor at How-To Geek. He has been using computers for 20 years --- tinkering with everything from the UI to the Windows registry to device firmware. Before How-To Geek, he used Python and C++ as a freelance programmer. In college, Nick made extensive use of Fortran while pursuing a physics degree. Nick's love of tinkering with computers extends beyond work. He has been running video game servers from home for more than 10 years using Windows, Ubuntu, or Raspberry Pi OS. He also uses Proxmox to self-host a variety of services, including a Jellyfin Media Server, an Airsonic music server, a handful of game servers, NextCloud, and two Windows virtual machines. He enjoys DIY projects, especially if they involve technology. He regularly repairs and repurposes old computers and hardware for whatever new project is at hand. He has designed crossovers for homemade speakers all the way from the basic design to the PCB. Nick enjoys the outdoors. When he isn't working on a computer or DIY project, he is most likely to be found camping, backpacking, or canoeing. A Pi-hole is a great way to block trackers, a few ads, and even some types of malware, like well-known phishing sites. However, the most surprising thing about running a Pi-hole is the amount of information you get almost instantly. You become privy to nearly every connection every device on your network makes. What Pi-hole actually is A DNS sinkhole that sees every request your network makes Normally, when your PC or phone tries to connect to a website on the Internet, it forwards the domain name to a DNS server, which returns an IP address. A Pi-hole works by selectively filtering those requests. First, you add a domain to a blocklist. When the Pi-hole sees a request for that domain, it never forwards the request to the regular DNS server. The device that made the request never gets an IP back, and the connection is effectively blocked. Because it sits between every device on your network and the wider internet, your Pi-hole necessarily sees every DNS lookup request made by devices on the network. That gives you an incredible amount of insight into what your devices are doing behind the scenes. Because DNS is extremely lightweight, you don't need an especially powerful machine to run a Pi-hole. You can run it comfortably on any Raspberry Pi, even a Pi Zero 2 W. The key distinction here is that, unlike a browser extension, Pi-hole protects devices you can't install software on, like your robovacuum, your game console, and your smart TV. Sometimes a DNS blocker breaks things; it also has limits Pi-holes are great for visibility and control, but they have a few drawbacks that you should be aware of. DNS blocking casts a pretty wide net. You will sometimes find that a website or app breaks unless you manually add the domain to an allowlist. You'll also find that DNS blocking can't block hardcoded IP addresses or devices using DNS-over-HTTPS (DoH). The query log tells all You probably don't realize just how many devices phone home The ad-blocking is a great perk, but the query log is the most informative part of a Pi-hole. When you start digging through the information to find the "Top Blocked Domains" dash, you aren't just seeing ads served to your PC; you're seeing a complete log of everything that tries to phone home from your network. Some common offenders are smart TVs pinging analytics servers every few minutes and phone apps connecting to unexpected servers in random countries while they aren't even in use. The single most surprising discovery on my network was my robotic vacuum. It phones home constantly and, in one 24-hour period, generated more queries by itself than my desktop PC did. If you're privacy-conscious—especially if you have kids—that kind of behavior can be concerning. Kids' tablets and apps aren't exempt; they're actually prime targets for this sort of snooping. You should run a Pi-hole if you have a house full of IoT devices, if you're a parent wanting visibility into what's happening on the network, or if you're simply privacy-conscious. Setting it up on a Raspberry Pi One command and a little bit of router configuration To get started, you'll need a Raspberry Pi, a microSD card, and a power supply. Ideally, you should use a Pi that has a physical Ethernet port—it provides a more stable connection than Wi-Fi. Flash Raspberry Pi OS Lite onto the microSD card using Raspberry Pi Imager, and make sure to enable SSH access. Insert your card into your Raspberry Pi, power it up, and then connect over SSH. Install Pi-hole using the automated installer. You'll have to make a few choices, so don't leave it completely unattended. The most important step is pointing your router's DHCP DNS setting at the Pi's IP address. Make sure to apply a static IP address to the Pi too—if you don't, your entire network will break when the Pi-hole's address changes. Once you do that, every device that joins your Wi-Fi is automatically covered without you having to configure each one individually. A Pi-hole is more than an adblocker Ad-blocking is usually the feature that draws people to the hardware, but the visibility the query log gives you will change how you handle smart devices. The first time you check your logs and realize just how much traffic was previously flying under the radar is eye-opening. That visibility allows you to make more informed decisions about which devices you buy and how much access you give them. From there, you can sometimes use the Pi-hole itself to block most of that traffic. Remember, the Pi-hole can also be used to block phishing sites and sites known to distribute malware. I'd strongly recommend it. It won't protect you from everything, but it gives you unmatched visibility into your network.