Winner
Price unavailable right now
Data from the official Google and X-Sense sites.
2026 verdict
House wiring and a full sensor suite against a small battery puck, and the Google Nest Protect (Wired) is the more complete smoke alarm by a clear margin.
It detects carbon monoxide as well as smoke, tests itself, filters shower steam with Steam Check, lights a pathlight at night and runs on mains power with a 3 AA backup. It also works with Google Home and Home Assistant and links to other Nest Protects over its own wireless interconnect. The X-Sense Wi-Fi Smoke Alarm is smoke only, but it needs no wiring, runs 10 years on its CR123A cell, sends Wi-Fi phone alerts, works with Home Assistant and carries a 5 year warranty against 2. Pick the Google Nest Protect (Wired) for a Google home with existing alarm wiring, and the X-Sense Wi-Fi Smoke Alarm for simple, wire-free smoke alerts.
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| Feature | Google Nest Protect (Wired) | X-Sense Wi-Fi Smoke Alarm | Winner |
|---|---|---|---|
| Rating | 4.6 | 4.3 | Google Nest Protect (Wired) |
| Warranty | 2 years | 5 years | X-Sense Wi-Fi Smoke Alarm |
| Connectivity | 2.4 GHz WiFi, Bluetooth, Other | 2.4 GHz WiFi | Google Nest Protect (Wired) |
| Integrations | Google Home, Home Assistant | Home Assistant | Google Nest Protect (Wired) |
| Sensors | Smoke, CO, Occupancy, Temperature, Humidity, Ambient Light, Motion | Smoke | Google Nest Protect (Wired) |
| Alerts | Fire Alerts, CO Alerts, Low Battery Alerts | Fire Alerts, Low Battery Alerts | Google Nest Protect (Wired) |
| Tests Itself | YES | NO | Google Nest Protect (Wired) |
| Pathlight | YES | NO | Google Nest Protect (Wired) |
| Steam Check | YES | NO | Google Nest Protect (Wired) |
| Screen | NO | NO | Tie |
| Built-in Siren | YES | YES | Tie |
| Built-in Light | YES | YES | Tie |
What the differences mean
Carbon monoxide
The Google Nest Protect (Wired) detects smoke and carbon monoxide. The X-Sense Wi-Fi Smoke Alarm detects smoke only, so a home with gas appliances would need a CO alarm next to it.
Power and installation
The Nest is hardwired to mains alarm wiring, with 3 AA batteries as backup, so it needs an existing wired alarm location. The X-Sense runs on a battery rated for 10 years and goes up anywhere with two screws.
Google Home
The Google Nest Protect (Wired) works with Google Home and Home Assistant. The X-Sense works with Home Assistant but not with Google Home, Alexa or Apple Home.
Self-test, Steam Check and pathlight
The Nest checks its own sensors, tells shower steam from smoke and lights your way at night using its motion sensor. The X-Sense has none of these and is tested by hand.
Size and warranty
The X-Sense is a 78 mm puck weighing 92g with a 5 year warranty. The Nest is a 134 mm square at 375g with a 2 year warranty.
Which one to buy if
- your ceilings already have hardwired alarm connections
The Google Nest Protect (Wired) runs on that wiring and keeps a battery only as backup.
- you need carbon monoxide detection too
Only the Nest senses CO; the X-Sense is smoke only.
- you have no alarm wiring and want an easy install
The X-Sense Wi-Fi Smoke Alarm is battery powered and needs no electrician.
- your smart home is built on Google Home
The Nest appears in Google Home; the X-Sense does not.
Winner
Price unavailable right now
- + Rating: 4.6
- + Connectivity: 2.4 GHz WiFi, Bluetooth, Other
- + Integrations: Google Home, Home Assistant
- - Warranty: 2 years vs 5 years
- + Warranty: 5 years
- - Rating: 4.3 vs 4.6
- - Connectivity: 2.4 GHz WiFi vs 2.4 GHz WiFi, Bluetooth, Other
What owners say
Owners of both alarms mention a quick setup through the app and the reassurance of phone alerts while away. Google Nest Protect (Wired) owners single out never hearing a low-battery chirp at 3am, the spoken warning that names the room before the horn, units that sound together even with Wi-Fi down, nightly self-checks and cutting the heat through a Nest thermostat when CO is detected. Their complaints are that it only interconnects with other Nest Protects, not the wired alarms already in the house, the cost of replacing every detector, a fixed list of room names and no Alexa or Apple Home. X-Sense Wi-Fi Smoke Alarm owners praise setup in minutes over Wi-Fi, a solid build and a replaceable battery, and they note there is no automatic self-test and that the app is only in English for some buyers.
Frequently Asked Questions
Which is better overall: Google Nest Protect (Wired) or X-Sense Wi-Fi Smoke Alarm?
The Google Nest Protect (Wired). It detects carbon monoxide as well as smoke, tests itself, filters steam, adds a pathlight and works with Google Home. The X-Sense Wi-Fi Smoke Alarm is the simpler, wire-free option with a 5 year warranty.
Does the X-Sense Wi-Fi Smoke Alarm work with Google Home?
No. The X-Sense Wi-Fi Smoke Alarm does not work with Google Home, Alexa or Apple Home; it sends alerts through the X-Sense app and works with Home Assistant. The Google Nest Protect (Wired) works with Google Home.
What is the biggest difference between the Google Nest Protect (Wired) and the X-Sense Wi-Fi Smoke Alarm?
The Google Nest Protect (Wired) is a hardwired smoke and CO alarm with self-testing and extra sensors, while the X-Sense Wi-Fi Smoke Alarm is a battery-powered smoke-only alarm.
Does the Google Nest Protect (Wired) need batteries?
It runs on house wiring and uses 3 AA batteries only as backup. The X-Sense Wi-Fi Smoke Alarm runs entirely on a CR123A battery rated for 10 years.
Who should buy the Google Nest Protect (Wired)?
Google and Nest households with hardwired alarm wiring that want smoke and CO detection, spoken warnings and an alarm that tests itself.
Who should buy the X-Sense Wi-Fi Smoke Alarm?
Renters and homeowners without alarm wiring who want smoke alerts on their phone from a small, long-lasting battery unit.
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Compare all 28 Smoke & CO Detectors side by side
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