To help you find the best smoke and carbon monoxide detector for your home, we researched all of the top models, researching for accurate detection capabilities, via high-quality sensors, long-lasting batteries and form factors that make the units easy to place just about anywhere in the house. Additionally, we were attracted to newer products with tech-forward features, such as integration with related apps and voice functionality that will let you know what is going on in your home. Today even the best smart light bulbs are packed with features. This is one of the best smart home devices that you can invest in.
The best product we researched was easily the Google Nest Protect Smoke + Carbon Monoxide Alarm (2nd Gen) which is embedded with extremely accurate sensors, making it excel at its stated job duties, which go a step further by telling you approximately where in the home the breach is coming from. It transmits data via Bluetooth or Wi-Fi to a related app, which we found extremely responsive and easy to use, and the included batteries last five years. Keep reading to learn more about the Google Nest Protect Smoke + Carbon Monoxide Alarm and the other items on this list. You can also read about the best smart outlet to upgrade your home even further.
Top 6 Best Smoke and Carbon Monoxide Detectors Compared
#1 Google Nest Protect Smoke + Carbon Monoxide Alarm (2nd Gen)
Award: Top Pick
WHY WE LIKE IT: Available in both wired and battery-powered models, with the latter boasting five years of battery life. Both models boast best-in-class sensors that can tell you where in the home any problems are coming from and these products integrate nicely with a fantastic app, easily making these our top pick.
- Five year battery
- Locates source of smoke or carbon monoxide
- App is easy to use
- Wired unit does not have battery backup
- Extremely expensive
- 2 year warranty ok, but lower than most on this list
The Google Nest Protect Smoke + Carbon Monoxide Alarm is designed from the ground up to keep you safe, with a suite of high powered sensors that not only let you know, within seconds, if you are experiencing a leak or fire, but where in the home the problem is coming from. The Nest Protect CO Alarm operates smoothly with a related smart home app, transmitting via Bluetooth or Wi-Fi, and is available in two separate models, one that is hardwired and one that is powered by batteries. The battery-powered model comes with six lithium batteries, which will get you five years of use right out of the box.
Though the sensors are rated to last for ten years, which is nice, the warranty is only for two years, which is okay, but lower than most other products on this list. Additionally, this is an extremely expensive product, which could be an issue if you have a large home you are looking to fill with multiple sensors. It’s a great addition to your other smart home and automation gear.
#2 Kidde Battery-Operated Smoke/Carbon Monoxide Alarm
Award: Honorable Mention
WHY WE LIKE IT: Boasts a great features to price ratio, with a voice alarm that lets you know exactly what the issue is, and a smartly designed battery latch that will not shut if the batteries have been installed incorrectly, further increasing the product’s safety rating. It also comes with a ten-year warranty, making this a product a fantastic value.
- 10 year warranty
- Alarm features human voice
- Installation is easy
- Ionization only
- Should change batteries twice a year
- Not compatible with Duracell batteries
The Kidde Battery-Operated Smoke/Carbon Monoxide Alarm comes with many of the same high-end features found in some of our top picks, while costing slightly less. This combo unit accurately detects both smoke and CO and the alarm features a human voice, which lets you know exactly what the problem is. We also liked the easy installation and the fact that the battery latch will not close if batteries have been put in improperly, taking away some of the guesswork. The 10 years of warranty is also tied for the longest on this list.
Though we found the sensors built-in with this product to be highly accurate, they are ionization-based, and not photoelectric, and experts say that the latter is slightly more accurate when it comes to smoke. Additionally, this is a traditional battery-powered unit and those batteries should be replaced around twice a year. As well as making your home safe, make it smarter with 6 of the best WiFi thermostats.
#3 Kidde Hardwired Smoke and Carbon Monoxide Detector Alarm
Award: Best Warranty
WHY WE LIKE IT: Hardwired product that contains battery backup, so you’ll be safe even when your home’s power goes out, with a 10-year warranty, which is tied with our number four pick for the longest. This is a great product with a great warranty.
- Battery backup
- Voice explains why alarm is going off
- Up to 24 units can be linked together
- Ionization only
- Installation requires some light wiring
- Test alarms can be loud
The Kidde Hardwired Smoke and Carbon Monoxide Detector Alarm comes with a lengthy ten-year warranty, which is tied for the longest available on this list. The product is hardwired but contains a battery backup, so you can be sure it’ll be receiving juice even if the power goes out in your home. The sensors are accurate and the alarm contains the use of a human voice, which lets you know exactly why the alarm is going off, which is useful. Additionally, up to 24 of these can link together, so when one alarm goes off somewhere in the house, they will all go off.
Though we found the sensors to be accurate in the detection of smoke and CO, this is an ionization-based product, and experts say photoelectric devices offer slightly better accuracy. Additionally, it requires some light wiring on the installation end, though nothing too unmanageable. You can also read about the best home security gear.
#4 X-Sense 10-Year Battery Combination Smoke Carbon Monoxide Alarm Detector
Award: Best Long-Term Protection
WHY WE LIKE IT: The X-Sense SC07 offers sensitive, reliable protection from both smoke and carbon monoxide with an easy-to-read LCD display, a powerful 10-year battery, and user-friendly installation. The alarm’s smart sensors and certifications give peace of mind for home safety, all in a sleek, modern design.
- 10-year sealed battery
- Advanced sensors for high sensitivity
- Easy installation with no rewiring needed
- Basic model; lacks Wi-Fi or wireless interconnectivity
- LCD turns off in standby mode, which may affect visibility
With a high-sensitivity photoelectric smoke sensor and an electrochemical CO sensor, the X-Sense SC07 is designed to detect hazards more accurately and faster than many standard alarms, alerting you to danger before it becomes critical. The unit includes a large, easy-to-read LCD screen that displays real-time CO levels (measured in parts per million), battery status, and working status, keeping you fully informed in case of any changes. The sealed 10-year lithium battery ensures the alarm remains powered without the need for replacements, a significant time-saver that also protects during power outages.
Installation is straightforward, with no need for rewiring; simply mount it on any wall or ceiling using the included bracket and screws. Certified by the highest safety standards, this alarm not only provides robust protection but also an effortless user experience. While this model does not support wireless interconnectivity or Wi-Fi, it’s perfect for homeowners who need reliable, independent alarms without complex setups.
#5 JNHCD Monoxide Audible Battery-Operated Detector
Award: Best Dual-Sensor Protection
WHY WE LIKE IT: Combining photoelectric smoke and carbon monoxide detection in one, this battery-powered alarm offers advanced sensitivity and a digital display for real-time monitoring. Easy to install and maintain, it’s a practical choice for home safety that delivers reliable alerts on potential dangers.
- Highly sensitive sensors detect smoke and CO accurately and quickly
- Digital display with ppm levels for proactive monitoring
- Battery-operated for installation flexibility
- Blue LED light may be noticeable in dark spaces
- Base attachment can be finicky during setup, though rarely adjusted after installation
This detector stands out for its dual photoelectric sensors, which are particularly sensitive to smoke and carbon monoxide, providing early alerts for potential risks in the home. The digital display adds a practical touch, showing real-time CO levels (in ppm) and smoke presence, helping you monitor air quality at a glance. Battery operation allows for easy, wire-free installation in key areas, and the unit is simple to test by pressing the “Test” button to make sure it’s in working order.
Once activated, a green LED light blinks every 60 seconds to confirm the unit’s functionality, providing peace of mind without frequent testing. Some users noted the blinking blue LED may be noticeable in bedrooms at night, so a hallway or common area placement might be preferable for those sensitive to light. Overall, its certified dual-sensor design and reliable battery backup make it a versatile and trustworthy choice for safeguarding against smoke and carbon monoxide.
#6 Lecoolife Smoke and Carbon Monoxide Detector
Award: Best Value Dual-Sensor Alarm
WHY WE LIKE IT: Equipped with both electrochemical and photoelectric sensors, this detector provides sensitive detection for both smoke and carbon monoxide, minimizing false alarms and maximizing safety. With a 10-year battery and a practical LCD display, it’s a reliable choice for home protection without the need for frequent maintenance.
- Two-pack provides extended coverage, ideal for larger homes or multi-room protection
- 10-year built-in lithium battery for continuous operation
- LCD screen shows real-time CO levels and battery life
- Wall mounting can be tricky, as alignment isn’t ideal for some setups
- Not UL-certified, which may be a consideration for buyers needing strict code compliance
The Lecoolife Smoke and Carbon Monoxide Detector provides two-in-one protection that combines photoelectric smoke detection and electrochemical CO sensing. This dual-sensor approach minimizes false alarms from cooking or steam while ensuring accurate and timely detection of real threats. The LCD display is a convenient feature, showing real-time CO concentration in parts per million (ppm) along with battery life, and it also lights up for high CO levels, making monitoring simple.
With a built-in lithium battery lasting 10 years, this detector is designed for long-term use without the hassle of frequent battery changes or chirping alarms, adding ease and peace of mind. Installation is straightforward for ceiling mounting, though wall-mounting may require some adjustment for alignment. While its affordable price and sensitive detection make it a valuable choice, the lack of UL certification is worth noting for those needing compliance. All in all, this Lecoolife detector is a practical, long-lasting solution for smoke and CO safety in the home.
How We Decided
To help you find the best smoke detector / carbon monoxide detector combo unit, we researched a multitude of products, researching for detection accuracy, with a mix of both ionization-based models and photoelectric models. We also populated the above list of the best carbon monoxide detectors with hardwired and battery-powered products, preferring hardwired models with battery backup, so as to increase peace of mind. After all, the best smart home devices should be simple and easy.
When something was battery-powered, we made sure you’d get a lot of use before having to replace the batteries. Most of the battery-powered products on this list can last nearly a year on one set of batteries, which is the industry standard, and our top pick can go five whole years before needing the batteries to be replaced.
We also favored products with some bells and whistles, like models that issue alerts via human voice, so you can know exactly what is going on, and those that feature advanced sensors that actually pinpoint where in the home any danger is coming from. Finally, we made sure each product boasted a long-lasting warranty of at least two years, with some ascending to seven and ten years. Speaking of smoke, the best air purifier for smoke will clean your air.
Smoke Detector / Carbon Monoxide Detector Buying Guide
The Most Important Features to Consider
- Sensors and Detection
These products are packed with sensors to accurately detect if there is a fire or a carbon monoxide leak in your home. These sensors typically fall into two categories. Ionization-based sensors are better at detecting flaming fires, while photoelectric sensors are better at detecting smoldering flames. Each have their uses, though experts have concluded in recent years that photoelectric sensors are slightly more accurate. Carbon monoxide detectors are usually tested against a low CO level@@ 100 parts per million and a high CO level@ 400ppm. - Power
These products are typically powered via two methods, hardwiring and batteries. The former connects to your home’s electricity and occasionally include battery backups, in case your power goes out. Battery-based models can last around a year before failure, but experts suggest that the batteries be changed twice a year, as a safety precaution. Some units allow for easy battery replacement, so you don’t have to remove the product from your ceiling, or wherever it is resting. - Additional Features
Some newer models boast some additional functionalities, including interacting with a related app, as with our top pick. Others use advanced sensors to approximate where in your home the danger is coming from, which can help you get things sorted out. Some detectors eschew loud chirps for the human voice, which is useful because it can announce exactly what is going on, taking away some of the guesswork.
