The Best Smart Smoke / CO Detectors and Monitors of 2024

Second to the Nest Protect, the Kidde Smoke and Carbon Monoxide Detector is one of the smartest we’ve tested. The device , available exclusively at Home Depot, offers a full spread of smart home functionality with Amazon Echo and Google Home, is simple to set up and use, and should last a decade before you need to replace it.

Installation requires existing wiring (120V AC). As long as you don’t run into any snags with your wires, the physical installation process is simple and takes about five minutes (don’t forget to flip off the breaker before you begin). A built-in lithium backup battery (estimated lifespan of 10 years) ensures that the monitor remains on during a power outage.

Like the Nest Protect, the Kidde detector uses voice warnings to alert you of fire or carbon monoxide instead of a traditional alarm tone. The alerts aren't as detailed as what's available on the Nest Protect, which tells you exactly what room or area of the home the problem is in. But the Kidde alerts are loud, easy to understand, and more calming than the blaring sounds put out by most other detectors. The device can also be interconnected with other Kidde smoke and carbon monoxide detectors for whole-home coverage.

Alerts are sent quickly in a variety of ways (push, SMS, and email). Voice assistants Alexa and Google Assistant can also alert you to smoke or carbon monoxide-related issues through Amazon Echo and Google Nest smart speakers and displays. You can also use either smart assistant to check the status of your detector. One thing that’s a bit unusual about the smart assistant setup is that you have to enable permissions between the detector and Alexa and/or Google Assistant in the Kidde app (in addition to adding the device to your smart home ecosystem).

The Kidde Smoke and Carbon Monoxide Detector may not be as feature-filled as the Nest Protect, but the device gets closer to achieving Google's helpful emergency smarts than most, and offers more versatility should you switch to Alexa. Kidde is also the more affordable of the two detectors, making it a mighty fine choice for anyone who doesn't want to pay a premium price for Nest.

The First Alert 2-in-1 Smoke and Carbon Monoxide Alarm (second-gen) is a good fit for smart homes with a Z-wave hub like the Ring Alarm or Samsung SmartThings. The detector, which runs on two included AA batteries, only connects over Z-Wave Plus, a low-frequency wireless signal that offers a broader coverage range and better connectivity than the first-gen Z-Wave alarm. To test the monitor, we paired it with the Z-wave-compatible Ring Alarm Pro base station. It took several attempts to add the device due to glitches in the Ring app, but forcing the app closed and reopening it multiple times did the trick.

The device detects smoke quickly, which triggers instantaneous push alerts to your phone and a loud, 85-decibel tone to start blaring from the detector. Base stations for Ring Alarms also double as sirens, which you can silence directly from the Ring app. There is no way to silence the detector from the app itself. This is one of the most frustrating aspects of the alarm, as you’ll always need a chair or ladder to reach up and silence it somehow.

The detector doesn’t work with Apple HomeKit or Google Home, but it is compatible with the Amazon Echo ecosystem. Supposedly the device can make announcements using Echo smart speakers and displays when the detector needs attention, but this feature did not work for us. However, between the push alerts and multiple alarm tones, it’s hard to miss any alarm events.

When you use the device with a Ring Alarm or Ring Alarm Pro base station (coupled with a paid Ring Protect Pro plan), emergency responders will be automatically notified by Ring's professional monitoring team when the device detects a problem at home. One advantage of pairing it with the Ring Alarm Pro, which has a built-in Wi-Fi router, is that it can keep the detector online even during a Wi-Fi outage. (The Ring Protect Pro plan is required to access the base station’s 24/7 internet backup service.)

Though it’s got a couple of setup and usability quirks, the First Alert 2-in-1 Smoke and Carbon Monoxide Alarm (second-gen) is a fantastic choice for smart homes reliant on Z-wave hubs.

The Abode Smoke Alarm Monitor gets top marks in terms of performance—it sends push notifications to your phone within seconds of hearing a smoke alarm go off and, unlike other monitors we tested, it also gives off a high-pitched siren of its own.

This battery-powered smoke alarm monitor is easy to install—you can either use screws or double-sided tape to mount the small unit on the ceiling near your existing smoke detectors. It’s also straightforward to pair with the associated app, which is intuitive and easy to use. You can quickly silence the monitor from the app, and we liked that this system sends out push notifications if it ever loses a Wi-Fi connection.

The major downside of this particular monitor is that it must be paired with the Abode Gateway, and the brand’s basic “Starter Kit” costs $199. However, if you already have the gateway or are interested in a DIY security system, this monitor would be a great choice.

If you’re looking for a smart smoke and carbon monoxide detector that has tons of functionality, the First Alert Onelink Safe & Sound is a good option that sends push notifications quickly. It also ha other features like a built-in Bluetooth speaker, customizable night light, and Alexa functionality.

During our testing, the Onelink Safe & Sound pushed out smartphone notifications as soon as the detector went off, and it was easy to silence alarms via the app. Both the voice announcements and speaker quality were impressive, but the Onelink app itself isn’t the best, crashing fairly frequently. Additionally, this smart smoke alarm was a challenge to install—it was nearly impossible to clip into the mount, and once you do get it in, it probably won’t come off.

Overall, this smart smoke and carbon monoxide detector is packed with smart features and does its main job well, alerting you immediately with push notifications if it ever goes off. However, it’s more expensive than others we tested, and a lot of the features that command its higher price seem kind of unnecessary. If you like the idea of using your smoke detector to play music or as an Alexa device, you can feel secure that this device will protect your home and family, but if the extraneous features don’t appeal to you, there are cheaper, equally reliable options, such as the Nest Protect.

The X-Sense Wi-Fi Smoke Detector is a compact, lithium battery-powered device that uses photoelectric sensors to detect smoke (but not carbon monoxide levels like others in our guide).

The device isn’t compatible with the Amazon Echo or Google Home ecosystems, but remote management is available in the TuyaSmart app for iOS and Android. The device doesn't have the intuitive features and helpful smarts of the Nest Protect, but the trade-off here is that it’s also one of the least expensive smoke detectors in our guide.

Some Amazon reviewers report difficulties connecting the device to Wi-Fi during setup. We didn’t have any connection issues (using a dual-band Eero Mesh Wi-Fi router), but the alarm does need a 2.4 GHz wireless network in order to work.

It took the X-Sense Wi-Fi Smoke Alarm several seconds longer to detect smoke than the Nest Protect, but alerts were sent quickly once the siren started to sound. The 85-decibel tone is loud enough to hear from a room over, but it is harder to hear if you’re across the house or in the garage. To remedy this, you can connect multiple X-Sense smoke alarms on the same Wi-Fi network, so that when one sounds, they all do. When the alarm goes off, a blinking red light on the alarm serves as a helpful visual clue.

In the X-Sense app, you can silence the alarm, view the alarm’s history, and review results from the device’s automatic self-checkups. One issue we experienced with that app is that it continued to show there was a fire danger after the smoke had cleared. It took a couple of minutes for the app to show that everything returned back to normal.

The alarm takes a CRR123A 3-volt lithium battery, which isn’t as common as the AA or 9V batteries you’ve probably got floating around your junk drawer. Low battery notifications are sent when it’s time to pop in a new one. Registering the device with X-Sense activates a seven-year warranty.

The X-Sense Wi-Fi Smoke Alarm falls short on features compared to other detectors in our guide, but it is one of the cheapest options.

We had high hopes for the second generation First Alert Onelink Smoke and Carbon Monoxide Detector, but this model had many of the same problems as the original version. This updated alarm is now compatible with Android phones (the first generation wasn’t), but the app still crashes and the pairing process is still clunky and glitchy.

Further, we found this smoke and carbon monoxide detector had connectivity issues. Several times when we tested it via the app or set it off with artificial smoke, the app never even registered the action. We spoke with Onelink support to resolve these issues, and they noted the detector can have problems if it’s too far from the Wi-Fi router or if there’s interference from other appliances. Overall, we just don’t feel confident recommending this product, as its smart features don’t seem to perform reliably and may not let you know if there's an emergency when you're not home.