Shelly i4 Gen3
Overview
Shelly i4 Gen3 is a Wi-Fi operated 4-digital-input controller designed for triggering scenes, automations, and complex actions without switching a load.
It allows you to use standard wall switches or buttons to control other Shelly devices, HTTP/MQTT endpoints, and automation platforms, making it ideal for advanced control logic behind existing switches.
Powered by the Gen3 Shelly ESP processor with 8 MB memory, Shelly i4 Gen3 delivers fast response times, improved reliability, and expanded integration support while fitting behind standard wall switches.
Key Features
• 4 digital inputs for scene and automation triggering
• Supports up to 16 actions via multi-click (short, long, double, etc.)
• Wi-Fi operated – no hub required
• New Gen3 ESP processor (ESP-Shelly-C38F) with 8 MB memory
• Immediate execution of actions and notifications
• Works with Shelly relays, sensors, scenes, and third-party systems
• Supports scripting (mJS), webhooks, MQTT, WebSocket, HTTPS, UDP, TLS
• Acts as a Wi-Fi range extender and Bluetooth gateway
• Bluetooth for fast onboarding and device inclusion
• Supports KNXnet/IP communication
• Compatible with Shelly Smart Control app, Home Assistant, Alexa, and other platforms
Technical Specifications
Power Supply
Power supply: 110–240 V AC ±10%, 50/60 Hz
Device power consumption: < 1 W
Inputs & Control
Channels: 4 digital inputs
Multi-click support: Up to 16 possible actions
Custom scripts (mJS): Yes
Device temperature protection: Yes
Connectivity
Wi-Fi protocol: 802.11 b/g/n (2.4 GHz)
Wi-Fi radio signal power: 1 mW
Wi-Fi range:
• Up to 50 m outdoors
• Up to 30 m indoors
Bluetooth: Yes
Bluetooth protocol: 4.2
Bluetooth range:
• Up to 30 m outdoors
• Up to 10 m indoors
Environmental
Operating temperature: -20°C to 40°C
Physical
Dimensions (H × W × D): 37 × 42 × 16 mm
Installation Notes
• Input-only device – does not contain relays or switch loads
• Designed to fit behind standard wall switches and control panels
• Requires external switches or buttons connected to the inputs
• Intended for triggering scenes, automations, and logic flows
• Can operate fully locally without cloud dependency
In the Box
• Shelly i4 Gen3
• Quick start guide