Kidde Smart Smoke & CO Detector with Ring vs Shelly Plus Smoke Alarm

Kidde Smart Smoke & CO Detector with Ring, because it detects carbon monoxide as well as smoke, sends low-level CO alerts and reduces cooking false alarms. Shelly Plus Smoke Alarm wins on price and on integrations, covering Google Home, Alexa, SmartThings and Home Assistant with MQTT.

No. Shelly Plus Smoke Alarm has a smoke sensor only, with no CO sensor and no CO alerts. Kidde Smart Smoke & CO Detector with Ring pairs photoelectric smoke detection with an electrochemical CO sensor and warns of low-level CO in the app before the siren sounds.

Shelly Plus Smoke Alarm, which works with Home Assistant, MQTT, Google Home, Alexa and SmartThings, so a smoke event can drive lights, locks or scripts locally. Kidde Smart Smoke & CO Detector with Ring works with the Ring app and Alexa devices only, with no Google Home, HomeKit, SmartThings or Matter.

Shelly Plus Smoke Alarm uses a CR123A cell rated for five years and carries a 3 year warranty. Kidde Smart Smoke & CO Detector with Ring runs on two included AA batteries and reports low-battery status through the Ring app, so the warning arrives on your phone rather than as a night-time chirp.

No. Both connect directly to 2.4 GHz Wi-Fi with no hub required. Kidde Smart Smoke & CO Detector with Ring adds a wire-free interconnect so all Kidde alarms in the home sound together, which Shelly Plus Smoke Alarm does not offer.

Home Assistant and MQTT users who want hub-free smoke sensors that plug into local automations, at a lower price, with a five year battery and a 3 year warranty. If carbon monoxide protection and nuisance-alarm filtering matter more, Kidde Smart Smoke & CO Detector with Ring is the better choice.