Install MultiGeiger V2

Flash the firmware straight from your browser — no command line.

2.  Plug the board in over USB, then:

Your browser can’t flash over USB. Use desktop Chrome or Edge (Web Serial isn’t available in Firefox, Safari, or on iOS/Android). This page must be served over HTTPS to flash. Open the hosted version rather than a local file.

3.  Connect it to WiFi after flashing

When flashing finishes, the device starts its own setup access point for about two minutes:

• Join the WiFi network named after the device — by default esp32-<number> (its unique chip ID, e.g. esp32-1234567), password ESP32Geiger.

• Browse to http://192.168.4.1/config to enter your WiFi credentials and the rest of the settings.

The board then reboots onto your network. From then on it updates over-the-air — no cable needed.

Need to recover a bricked or mis-flashed board? Pick the board above and flash again — the merged image rewrites the bootloader and partition table from scratch. If the device won’t enter download mode automatically, hold its BOOT button while pressing RESET, then release BOOT.