ESP32 blocks 537,000 domains with about 50 KB of RAM
Published on July 20, 2026, the post describes ESP32 firmware that keeps a blocklist in flash and blocks requests in about 10 milliseconds, according to the post.
A post published on July 20, 2026 describes custom firmware for an ESP32 ad and tracker blocker. According to the post, it uses a list of 537,000 domains stored in flash, consumes about 50 KB of RAM, and blocks requests in approximately 10 milliseconds.
The example illustrates how flash can let a device with limited RAM consult a large list. To check the figures and understand the methods and limitations, consult the original post and verify whether it provides measurements and test conditions; the figures here are those reported by the publication. If you use AI to study or apply the idea, avoid putting confidential organizational data in the prompt.