Smoke alarms and carbon monoxide (CO) detectors warn you of imminent danger in your home, so you can get out as soon as possible. As such, they are essential life-safety devices. A smart smoke alarm or CO detector will alert you to danger from smoke, fire, or a malfunctioning appliance even when you’re not home. As such, they can not only save your life, they can also protect what is likely to be your single biggest financial investment. Smart smoke and CO detectors are among the most useful categories of smart home gear because they offer critical advantages over dumb versions of the same product.
Once installed and powered up, you download the relevant app and connect to the device wirelessly. Then, when the alarm goes off, not only do you receive an audio alert—many include helpful voice instructions as well as a siren—your smartphone also tells you what the problem is (whether it’s smoke or CO, which alarm was activated, and sometimes even the severity of the smoke).
Many smart smoke detectors hook into additional smart home gear and IFTTT, so an alarm can trigger your smart lighting to flash or change color when danger is detected. Perhaps the biggest benefit of a smart smoke detector: No more hunting down midnight chirps, since you’ll also get phone-based notifications about dying batteries.
Here are our picks for the best options on the market today.
Updated September 12, 2022 to add a link to our Kidde Smoke + Carbon Monoxide Alarm with Indoor Air Quality Monitor review.
Our top picks in smart smoke detectors
Nest Protect — best smart smoke alarm overall
- Clear and versatile alerts
- Dead-simple, foolproof app
- Works with a variety of other products if you have other Nest gear
- Quite expensive, but not at the top of the market
The Nest Protect is one of the most mature smart smoke alarms on the market, and it’s a no-brainer of a choice if you want one of the most sophisticated and reliable smart smoke detectors out there. Alarms are varied, integrated lighting is color-coded based on the type of threat, and the product includes helpful voice alerts when activated. In testing, our phone was alerted almost immediately, and the app couldn’t be simpler to master.
Kidde Smart Detection Smoke + Carbon Monoxide Alarm — Best smart smoke detector overall, runner-up
- An affordable step above “dumb” detectors
- Emits voice warnings for fire and carbon monoxide danger, in addition to beeps
- Compatible with existing interconnected Kidde detectors
- Nuisance alarms can be silenced in the smartphone app
- Must be hardwired for power as well as interconnect to other alarms
- No wireless interconnect features
- Voice commands are for system status only
- Setup instructions could be better
Adding wireless features to your smoke and carbon monoxide detection system is one of the best smart home investments you can make, and Kidde’s solution won’t break the bank.
X-Sense XS01-WT Wi-Fi smoke alarm — Best budget-priced smart smoke detector
- Handsome, petite design
- Easy setup and intuitive operation
- Compellingly low price
- Does not detect carbon monoxide
- Units cannot be interconnected
- No support for voice assistants
The X-Sense XS01-WT isn’t nearly as smart as the Nest Protect or Kidde products. It won’t warn you of dangerous levels of carbon monoxide in your home, and you can’t interconnect multiple units so that when one sounds off, they’ll all sound off. But its $40 list price makes it a compelling home-safety value.
What do I need to know about smart smoke detectors?
For the most part, smart smoke alarms tend to work almost identically. The device installs on the ceiling or high on the wall (typically replacing an old-school smoke alarm in the same location), either using batteries or in-wall power. Most of the smart smoke alarms we evaluated are available in either format and cost the same. When shopping, pay close attention so you don’t end up with the wrong type.
If you’re upgrading a hardwired model, it’s important that you replace all the detectors in the chain with the same make and model. One of the reasons for hardwiring a smoke detector is that if one detects a dangerous condition, it can trigger all the others to go off. But there’s no guarantee that feature will work if you have a mix of devices from different manufacturers wired together.
What should I look for when shopping for a smart smoke detector
Smoke and CO: Your home needs to warn against the danger of carbon monoxide as well as smoke. Some detectors will do both, so you don’t need to deploy–and monitor the batteries in–more than one device.
Detector sensitivity and accuracy: It’s very difficult to scientifically test how well a smoke/CO detector does its primary job without actually burning your house down. That said, simulating smoky conditions can reveal a little about how sensitive a detector is. As well, you can consider the general consensus about the underlying technology in a smoke detector. The Nest Protect, for example, uses a photoelectric split-spectrum sensor that is considered superior to the ionization sensor used in many older devices and which is more prone to false alarms.
Notification variety: A loud siren is expected, but voice alerts are quite handy: They not only tell you what type of hazard has been detected, but also alert you to its location and can even tell you how to respond (whether that’s opening a window or calling 911). Color-coded lights on the alarm itself are another plus. And, of course, speedy push notifications to your phone are a must in the smart alarm space.
Multiple users: Obviously you’re safest if more than one person receives a push alert that there’s a fire in the house. Look for a system that supports multiple users through an invitation system.
Interconnectivity: Some devices support an interconnectivity feature, so if one alarm goes off, all the other alarms in the house will go off as well. This can be a big benefit if you have a very large home and fear you might not hear an alarm going off elsewhere in the house. We didn’t test interconnectivity features in our review since we tested single alarms individually, so check specifications when shopping if this feature sounds useful.
Smart home hub support: If you want to integrate your smoke alarm with the rest of your home, consider whether it is supported by a major smart home hub. The Nest Protect is obviously tied to the Nest ecosystem, but Alexa, SmartThings, and HomeKit options are also available. Note that we had lackluster results with several of these hooks—and even if you do connect the alarm to your smart home hub, the ultimate usefulness of this connection can be limited.
That said, when paired with a smart thermostat, some smart smoke alarms can trigger the thermostat to shut down your HVAC system, so that smoke isn’t pulled into your ventilation system and circulated all around your home.
What other smart smoke detectors has TechHive reviewed?
Our X-Sense Mini review reports that those sensors can wirelessly interconnected, and you can buy a 3-pack for less than $60 on Amazon. But they don’t have any smart features beyond that; there’s no smartphone app, for instance, and the sensors don’t connect to your Wi-Fi network. That means they can’t alert you to a fire if you’re away from home. It’s also worth noting they won’t detect the presence of dangerous levels of carbon monoxide. You’ll find that street prices have dropped considerably since we published our First Alert Onelink Safe & Sound review, and it offers plenty of whizbang features, including the ability to operate as an Apple AirPlay 2 speaker–or Alexa-powered smart speaker–and it’s HomeKit compatible. But it remains the most expensive smart smoke and CO alarm we’ve reviewed. If you want HomeKit compatibility for less dough, check out our First Alert Onelink review. It keeps that feature but drops the music-streaming and smart speaker elements.