ESP32 board becomes cheapest home upgrade

MakeUseOf published a May 16 article arguing that a low-cost ESP32 board can serve as a network-wide ad and tracker blocker, using open-source firmware instead of a Raspberry Pi or an always-on old computer. The article pointed readers to ESP32_AdBlocker, a GitHub project that turns an ESP32 into a DNS sinkhole. The setup works by intercepting domain lookups on a home network and returning a non-routable address for domains on a blocklist. The result is a Pi-hole-style filter built around hardware that MakeUseOf said can cost about $5. ### What exactly is the board doing on a home network? ESP32_AdBlocker says the firmware acts as a DNS sinkhole by returning `0.0.0.0` for blocked domains and forwarding other requests to an external DNS resolver. That means ads and trackers can be stopped at the domain lookup stage, before content is loaded on phones, laptops, TVs or other devices connected to the same network. The GitHub project also says it includes a web server for control and monitoring. (makeuseof.com) MakeUseOf described the same mechanism in consumer terms, saying the ESP32 sits in the DNS path after a router is pointed at it. In that setup, devices on the network continue to browse normally for allowed domains, while requests to listed ad or tracking domains are dropped. ### Why are people comparing it with Pi-hole? (github.com) MakeUseOf framed the ESP32 option as an alternative for users who do not want to buy a Raspberry Pi or leave an older PC running full time. The article said a Raspberry Pi setup can cost roughly $60 to $100, while the ESP32 route starts far lower. Adafruit made a similar comparison in its ESPHole guide, which described an ESP32-S2-based ad blocker as a simpler, more available option than a Raspberry Pi-based Pi-hole setup. (makeuseof.com) Adafruit said its project was based on earlier ESP32 ad-blocking work and customized for one of its own Feather boards. ### What hardware does the project actually require? (makeuseof.com) The GitHub repository says the main requirement is an ESP32 module with PSRAM. It says an ESP32-S3 with 8MB of PSRAM can host a current-sized blocklist, while a 4MB PSRAM ESP32 may truncate a current-sized list. MakeUseOf also told readers to look specifically for boards with PSRAM, saying that is the memory used to hold the blocklist. (learn.adafruit.com) The repository says the software is delivered as an Arduino sketch. MakeUseOf said users flash the sketch onto the board, connect it to the network, and then point the router’s DNS settings to the device. ### How fast is it, and what are the trade-offs? ESP32_AdBlocker says blocklist checks take less than 50 microseconds on an ESP32-S3 and less than 100 microseconds on a 4MB PSRAM ESP32. (makeuseof.com) The project says that after first power-up, the default blocklist is downloaded and can take several minutes to process and sort before the device is ready. The same repository says the device downloads one consolidated blocklist file, supports HOSTS or Adblock formats, and can refresh that list daily at a set time. (makeuseof.com) Users can also add custom domains to block or allow. Those constraints mean the setup is lighter than a full Linux box, but it also depends on memory size and a single selected blocklist file. ### Where would a reader go next if they wanted to build one? (github.com) GitHub is the next stop for anyone trying the setup, because the ESP32_AdBlocker repository contains the firmware and hardware requirements. MakeUseOf’s article serves mainly as a consumer-facing walkthrough and buying prompt, while the repository provides the implementation details, including PSRAM guidance, supported blocklist formats and update behavior. (github.com) Adafruit’s ESPHole guide remains a separate, board-specific example for users who want a documented ESP32-based ad-blocking build with listed parts. As of the latest repository page, ESP32_AdBlocker was publicly available on GitHub and showed version 3.1 updated last month. (github.com) (makeuseof.com)