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ESP32-C3 Adblock is a Pi-hole-style DNS ad-blocker that runs on minimal hardware without requiring PSRAM. It stores 140,000+ domains as sorted 40-bit hashes in flash memory and uses binary search for lookups, consuming only ~50 KB of RAM while answering blocked queries in ~10 milliseconds.

Designed for users wanting network-wide ad blocking on budget hardware. The project demonstrates an alternative storage approach: instead of keeping domain strings in RAM, it hashes domains and stores them in flash, enabling the same blocking capability on cheaper microcontrollers. Works on ESP32-C3 boards and classic ESP32 variants.