ESP-01 Relay V4.0 Relay Board
ESP-01 Relay V4.0

Available from:


Flashed with:
Serial port

GPIO #Component
GPIO00 Relay_i 1
GPIO01 Led_i 1
GPIO02 None
GPIO03 Button 1
GPIO04 None
GPIO05 None
GPIO09 None
GPIO10 None
GPIO12 None
GPIO13 None
GPIO14 None
GPIO15 None
GPIO16 None
Template for Tasmota v9.1+

This works without hardware modification on the v4.0 module, but you can add a switch from RX to GND as an On/Off switch.

How to flash ESP-01(S)

There is no add in for the button on the module as it serves as a reset, rather than an on/off switch.

To make this work with v1.0 of the ESP-01 Relay, you must remove R2 (desolder it or just break it off with a screwdriver) and pull CH_PD high (this is easiest to do with a 10k resistor): https://i.imgur.com/79ySGMt.jpg