# Sonoff MINIR4 Extreme

> Ultra-compact ESP32-C3 WiFi smart switch module with 10A relay, detached switch mode, and the smallest form factor in its class. Fits any wall box. Flashable with Tasmota for local control.

## Quick Facts

- **Brand:** Sonoff
- **Board Type:** relay-module
- **Price:** ~$9.99
- **Product Readiness:** consumer
- **CPU:** ESP32-C3
- **CPU Architecture:** RISC-V
- **CPU Cores:** 1
- **RAM:** 400KB SRAM
- **Flash:** 4MB
- **Power:** 100-240V AC
- **Operating Voltage:** 3.3V
- **Antenna:** built-in PCB antenna

## Connectivity

- **Wifi:** 802.11 b/g/n
- **Bluetooth:** BLE 5.0

## Open Source

- **Firmware:** No
- **Schematics:** No
- **PCB Layout:** No

## Compatible Firmware

eWeLink, tasmota, esphome

## Use Cases

- home-automation
- smart-switch
- light-control
- retrofit-switch

## Components

- **ESP32-C3** (Microcontroller): Single-core 32-bit RISC-V microcontroller at 160MHz with integrated WiFi 802.11 b/g/n and Bluetooth 5.0 LE — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.espressif.com%2Fsites%2Fdefault%2Ffiles%2Fdocumentation%2Fesp32-c3_datasheet_en.pdf&ref=openhardware.directory&product=sonoff-minir4-extreme&source=md-export)
- **10A Relay** (Relay): Single-pole single-throw relay rated for 10A at 240V AC, suitable for most household lighting and appliance loads — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fsonoff.tech%2Fproduct%2Fdiy-smart-switches%2Fminir4%2F&ref=openhardware.directory&product=sonoff-minir4-extreme&source=md-export)
- **AC-DC Converter** (Power Supply): Integrated 100-240V AC to 3.3V DC converter powering the ESP32-C3 module — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fsonoff.tech%2Fproduct%2Fdiy-smart-switches%2Fminir4%2F&ref=openhardware.directory&product=sonoff-minir4-extreme&source=md-export)

## Protocols

- **WiFi 802.11 b/g/n**
- **Bluetooth 5.0 LE**
- **MQTT**

## Description

# Sonoff MINIR4 Extreme

The Sonoff Mini Extreme (MINIR4) is one of the smallest WiFi smart switch modules available, designed to fit inside virtually any wall switch box. Based on the ESP32-C3, it supports detached switch mode where the physical switch acts as a scene trigger independent of the relay.

## Key Features

- **ESP32-C3** RISC-V with WiFi and Bluetooth LE
- **10A/240V relay** for most household loads
- **Ultra-compact** — 39.5×33×16.8mm, fits any switch box
- **Detached switch mode** — physical switch independent of relay state
- **External switch input** — supports toggle, momentary, and doorbell switches
- **100-240V AC** input (neutral wire required)

## Tasmota Compatibility

- Flash via serial (requires opening the case and soldering)
- ESP32-C3 based — use `tasmota32c3` binary
- Full relay and switch control with rules support
- MQTT and Home Assistant auto-discovery

## Use Cases

- Retrofit smart light switching behind existing wall switches
- Doorbell notification with MQTT
- Bathroom fan timer with rules
- Garage door momentary pulse control

## Where to Buy

- [Buy for $9.99](https://openhardware.directory/r?to=https%3A%2F%2Fitead.cc%2Fproduct%2Fsonoff-minir4-extreme-smart-switch%2F&ref=openhardware.directory&product=sonoff-minir4-extreme&source=md-export)

## Resources

- [product](https://openhardware.directory/r?to=https%3A%2F%2Fsonoff.tech%2Fproduct%2Fdiy-smart-switches%2Fminir4%2F&ref=openhardware.directory&product=sonoff-minir4-extreme&source=md-export)
- [wiki](https://openhardware.directory/r?to=https%3A%2F%2Ftemplates.blakadder.com%2Fsonoff_MINIR4.html&ref=openhardware.directory&product=sonoff-minir4-extreme&source=md-export)
- [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2Farendst%2FTasmota&ref=openhardware.directory&product=sonoff-minir4-extreme&source=md-export)

## Tags

`esp32-c3`, `wifi`, `bluetooth`, `tasmota`, `esphome`, `relay`, `smart-switch`, `home-automation`, `sonoff`, `compact`

## Images

![Sonoff MINIR4 Extreme](https://nbg1.your-objectstorage.com/openhardware-directory/entities/sonoff-minir4-extreme/21b9cf5ab76d.jpg)
![Sonoff MINIR4 Extreme](https://nbg1.your-objectstorage.com/openhardware-directory/entities/sonoff-minir4-extreme/394389897fa2.jpg)
![Sonoff MINIR4 Extreme](https://nbg1.your-objectstorage.com/openhardware-directory/entities/sonoff-minir4-extreme/b0bf876b408a.jpg)
![Sonoff MINIR4 Extreme](https://nbg1.your-objectstorage.com/openhardware-directory/entities/sonoff-minir4-extreme/196583c8dae0.jpg)
![Sonoff MINIR4 Extreme](https://nbg1.your-objectstorage.com/openhardware-directory/entities/sonoff-minir4-extreme/cfc0007b6471.jpg)
![Sonoff MINIR4 Extreme](https://nbg1.your-objectstorage.com/openhardware-directory/entities/sonoff-minir4-extreme/d53538f9c965.jpg)

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