Carbon monoxide (CO) detectors monitor the air in your home and alert you when dangerous levels of this poisonous gas are present. Because carbon monoxide is an odorless, colorless gas, alarms can provide critical warning before symptoms of poisoning occur. Many modern models also offer features like digital displays, battery backups, and combination smoke detection.
To help you choose the right option for your home, we compared some of the most popular carbon monoxide detectors on Amazon.
Key Takeaways
- Carbon monoxide detectors help alert you to dangerous levels of carbon monoxide, an odorless, colorless gas produced by fuel-burning appliances and equipment, in your home.
- Base carbon monoxide detector models typically cost $30–$70, while dual smoke-and-CO models or portable units range from $70–$150.
- When shopping for a carbon monoxide detector, consider factors like power source, sensor technology, and warranty coverage.
Top 5 Carbon Monoxide Detectors
Here’s our list of the best carbon monoxide detectors on Amazon:
- First Alert Combination Smoke & Carbon Monoxide Alarm: Best Overall
- Kidde Nighthawk Carbon Monoxide Detector: Best Plug-In
- X-Sense Smoke and Carbon Monoxide Detector: Best Long-Life Battery
- X-Sense Interconnected Smoke and Carbon Monoxide Detector: Best Whole-Home Protection
- Kidde Carbon Monoxide Detector: Best Portable
Compare Top Carbon-Monoxide Detectors
Compare the best carbon monoxide detectors based on alert type, design, and more below.
| Product | Detection | Power Source (Volts) | Alert Type | Service Life |
|---|---|---|---|---|
First Alert Combination Smoke & Carbon Monoxide AlarmCheck Price | Smoke and carbon monoxide | 9V battery | Visual and auditory | 10 years |
Kidde Nighthawk Carbon Monoxide DetectorCheck Price | Carbon monoxide | Plug-in with 9V battery backup | Visual and auditory | 10 years |
X-Sense Smoke and Carbon Monoxide DetectorCheck Price | Smoke and carbon monoxide | Sealed 10-year battery | Visual and auditory | 10 years |
X-Sense Interconnected Smoke and Carbon Monoxide DetectorCheck Price | Smoke and carbon monoxide | Sealed 10-year battery | Visual and auditory | 10 years |
Kidde Carbon Monoxide DetectorCheck Price | Carbon monoxide | AA batteries | Visual and auditory | 10 years |
Our Reviews of the Best Carbon Monoxide Detectors
We compared the top carbon monoxide detectors to find the best options on Amazon for home safety, convenience, and value.
Best Overall
First Alert Combination Smoke & Carbon Monoxide Alarm
Good for: Reliable smoke and carbon monoxide protection in a single detector
The First Alert Combination Smoke & Carbon Monoxide Alarm combines smoke and carbon monoxide detection into a single battery-powered unit, helping reduce the number of alarms needed throughout your home. The device features First Alert’s Precision Detection technology, which is designed to reduce nuisance alarms from cooking while still providing early warning of potential hazards. The alarm also includes a test and silence button and an end-of-life warning that alerts you when it’s time for a replacement.
Pros and Cons of First Alert Combination Smoke & Carbon Monoxide Alarm
- Provides both smoke and carbon monoxide detection in one unit
- Battery-powered design allows for flexible placement and easy installation
- Includes “Precision Detection” technology to help reduce nuisance alarms
- Some customers report false alarms or reliability concerns
- Not compatible with certain older mounting brackets
Key Features
- Detection: Smoke and carbon monoxide
- Power Source: Battery-powered (9V battery included)
- Warranty: Limited 10-year warranty
What People Are Saying About The First Alert Combination Smoke & Carbon Monoxide Alarm
Many Amazon reviewers like this detector for its easy installation, reliable performance, and convenient combination of smoke and carbon monoxide protection. Customers also appreciate the included battery and straightforward testing process. However, some users report false alarms or compatibility issues when replacing older First Alert models.
Best Plug-In Detector
Kidde Nighthawk Carbon Monoxide Detector
Good for: Continuous plug-in protection with a digital carbon monoxide readout
The Kidde Nighthawk Carbon Monoxide Detector plugs directly into a standard wall outlet and includes a battery backup to provide protection during power outages. The device’s digital LED display shows current carbon monoxide levels, while peak level memory records the highest reading detected since the last reset. You can also mount the detector on a wall or place it on a tabletop using the included power cord.
Pros and Cons of Kidde Nighthawk Carbon Monoxide Detector
- Digital display provides real-time carbon monoxide readings
- Includes a 9V battery backup for protection during power outages
- Offers flexible placement with plug-in, tabletop, and wall-mount options
- Some customers report battery issues or defective units
- Larger size may seem more noticeable than compact detectors
Key Features
- Detection: Carbon monoxide
- Power Source: Plug-in with 9V battery backup
- Warranty: Limited 10-year warranty
What People Are Saying About The Kidde Nighthawk Carbon Monoxide Detector
Reviewers appreciate the detector’s digital display, which allows homeowners to monitor carbon monoxide levels at a glance. Amazon customers also like the plug-in design with battery backup and describe the unit as dependable and easy to install. Some users, however, have experienced battery-related issues or reported receiving defective units.
Best Long-Life Battery
X-Sense Smoke and Carbon Monoxide Detector
Good for: A low-maintenance detector with a sealed 10-year battery
The X-Sense Smoke and Carbon Monoxide Detector combines smoke and carbon monoxide detection in a single unit powered by a sealed 10-year lithium battery. It uses a photoelectric smoke sensor and an electrochemical carbon monoxide sensor for dual-threat protection, while an LCD display provides real-time readings and system status updates. The battery-powered design also allows for installation without wiring.
Pros and Cons of X-Sense Smoke and Carbon Monoxide Detector
- Combines photoelectric smoke detection and electrochemical carbon monoxide detection
- Includes a sealed 10-year battery that eliminates routine battery replacements
- LCD display shows current gas levels, battery status, and operating information
- Does not support Wi-Fi or wireless interconnection
- Some customers report false alarms or reliability concerns
Key Features
- Detection: Smoke and carbon monoxide
- Power Source: Sealed 10-year lithium battery
- Warranty: 10-year battery life
What People Are Saying About The X-Sense Smoke and Carbon Monoxide Detector
The X-Sense detector earns positive feedback for its sealed 10-year battery, compact design, and simple installation process. Many Amazon customers appreciate the detector’s low-maintenance design, which eliminates the need for regular battery replacements. On the downside, a small number of reviewers have reported false alarms, battery warnings, or concerns about long-term reliability.
Best Whole-Home Protection
X-Sense Interconnected Smoke and Carbon Monoxide Detector
Good for: Larger homes that need interconnected alarms across multiple floors
The X-Sense Interconnected Smoke and Carbon Monoxide Detector uses wireless interconnection technology to link up to 18 compatible alarms throughout a home. When one alarm detects smoke or carbon monoxide, all connected units sound simultaneously, helping alert occupants even if the danger starts on another floor. The detector also combines a photoelectric smoke sensor, an electrochemical carbon monoxide sensor, and a sealed 10-year battery in a single maintenance-free unit.
Pros and Cons of X-Sense Interconnected Smoke and Carbon Monoxide Detector
- Combines smoke and carbon monoxide detection in one unit
- Includes a sealed 10-year battery that requires no replacement
- Wirelessly connects with up to 18 compatible X-Sense alarms
- No Wi-Fi connectivity or smartphone alerts available
- Some customers report false alarms and battery-related issues
Key Features
- Detection: Smoke and carbon monoxide
- Power Source: Sealed 10-year lithium battery
- Warranty: 10-year battery life
What People Are Saying About The X-Sense Interconnected Smoke and Carbon Monoxide Detector
Amazon customers often cite the detector’s wireless interconnection feature as its biggest advantage, noting that all units sound alarms simultaneously when one detects a threat. Reviewers also appreciate the easy setup process and maintenance-free battery design. However, some users report false alarms, premature battery issues, or difficulties obtaining warranty support.
Best Portable
Kidde Carbon Monoxide Detector
Good for: Buyers who want portable carbon monoxide protection on the go
The Kidde Carbon Monoxide Detector is a battery-powered unit designed for flexible placement in bedrooms, hotel rooms, vacation rentals, and other living spaces. Its compact design can sit on a tabletop or get mounted on a wall without requiring wiring, while an electrochemical sensor monitors for dangerous carbon monoxide levels. The detector also features LED status indicators, a test and hush button, and an 85-decibel alarm.
Pros and Cons of Kidde Carbon Monoxide Detector
- Can get mounted on a wall or placed on a tabletop
- Compact, battery-powered design is easy to take while traveling
- Includes a loud 85-decibel alarm and visual status indicators
- Does not include a digital display showing carbon monoxide levels
- Some customers report receiving defective units or reliability concerns
Key Features
- Detection: Carbon monoxide
- Power Source: Two AA batteries
- Warranty: Limited 10-year warranty
What People Are Saying About The Kidde Carbon Monoxide Detector
Customers like this detector for its portability, simple setup, and dependable day-to-day performance. Many reviewers appreciate the combination of continuous plug-in power and battery backup during outages. noting that it works well both at home and while traveling. However, some customers have reported receiving defective units, error messages, or concerns about detection thresholds and long-term reliability.
Carbon Monoxide Detector Buying Guide
Carbon monoxide detectors help alert you to the presence of this odorless, colorless gas before it reaches dangerous levels in your home. Most carbon monoxide detectors cost between $30–$70, while premium models with features like combination smoke detection, wireless interconnectivity, digital displays, or portable designs can cost $70–$150.
Before choosing a detector, consider factors like its power source, detection capabilities, alert system, and service life.
Power Source
Carbon monoxide detectors typically come in three main power configurations:
- Battery-powered: Battery-operated detectors are easy to install and continue working during power outages. Some models use replaceable batteries, while others include sealed lithium batteries designed to last up to 10 years.
- Plug-in: Plug-in detectors connect to a standard wall outlet and often include battery backup protection. These models eliminate routine battery changes while maintaining protection during outages.
- Hardwired: Hardwired detectors connect directly to your home’s electrical system and typically include battery backup. These models are common in newer homes and can often interconnect with other alarms throughout your house.
Detection Type
Some detectors monitor only carbon monoxide, while others combine multiple safety functions at once. The right choice depends on your home’s existing smoke alarm setup, local building code requirements, and whether you’re looking to minimize the number of devices installed throughout your home.
Dedicated detectors monitor carbon monoxide levels and are often smaller and more affordable than combination units. These models offer a good option if your home already has up-to-date smoke alarms or if you need additional carbon monoxide protection in a specific area, like near a furnace, water heater, or attached garage.
Combination units detect both smoke and carbon monoxide, reducing the number of devices needed throughout your home. These detectors can simplify installation and maintenance while providing protection against two common household hazards. Many newer combination models also include advanced smoke-sensing technology, like photoelectric sensors, to help reduce nuisance alarms.
Sensor Technology
The sensor inside a carbon monoxide detector determines how the device identifies potential hazards. Most modern carbon monoxide detectors use electrochemical sensors, which are designed to accurately detect carbon monoxide while minimizing false alarms.
If you’re purchasing a combination smoke and carbon monoxide detector, pay attention to the smoke sensor type as well. Many newer models use photoelectric smoke sensors, which are generally more responsive to slow-smoldering fires and less prone to nuisance alarms from cooking than traditional ionization sensors. Some detectors use a combination of sensor technologies to provide broader protection against smoke and carbon monoxide.
Alert Features
A detector’s alert system can make it easier to identify potential hazards quickly.
Most carbon monoxide detectors use an alarm rated at approximately 85 decibels, which is loud enough to wake sleeping occupants. Look for a detector that you can hear from bedrooms and other frequently occupied areas of your home.
Many models include LED status lights that show whether the alarm is operating normally or has detected a problem. These indicators can also help identify low-battery or maintenance alerts.
Some detectors feature LCD screens that display current carbon monoxide levels, battery status, or system information. A digital display can provide additional context during an alarm and help homeowners monitor low-level carbon monoxide readings that may not trigger the alarm.
Interconnectivity
Large homes may benefit from interconnected detectors. When one alarm detects smoke or carbon monoxide, all connected alarms sound simultaneously, helping ensure occupants hear the alert regardless of where they are in the home. You can set up interconnection through hardwired connections or wireless communication between compatible detectors.
Some advanced detectors also include smart features, like mobile app notifications, remote monitoring, and smart home integration. While these features can provide additional convenience, many homeowners find that interconnected alarms offer sufficient whole-home protection without requiring Wi-Fi or app connectivity.
Service Life and Maintenance
Most carbon monoxide detectors have a service life of five to 10 years before the sensor needs replacement. Many newer models use sealed 10-year batteries that eliminate routine battery changes and help reduce maintenance. Look for detectors with end-of-life notifications that alert you when it’s time to replace the unit. Regardless of battery type, test your detector monthly and replace the entire unit once it reaches the end of its rated service life.
How Do You Install a Carbon Monoxide Detector?
Installing a carbon monoxide detector is usually a straightforward do-it-yourself (DIY) project, though the process varies depending on the detector’s power source.
Battery-powered detectors are the easiest to install. Most mount to a wall or ceiling using the included bracket and screws, then activate once the batteries are inserted or the unit is attached to the mounting plate.
Plug-in detectors simply connect to a standard electrical outlet and often include battery backup protection. These models are ideal for homeowners who want simple installation without worrying about routine battery changes.
Hardwired detectors connect directly to your home’s electrical system and may require replacing an existing alarm or adding new wiring. If you’re not comfortable working with electrical connections, consider hiring a licensed electrician for installation.
Regardless of the type of detector you choose, follow the manufacturer’s placement recommendations and test the device after installation to ensure it’s operating properly.
Where Should You Install Carbon Monoxide Detectors?
For the best protection, install carbon monoxide detectors on every level of your home and outside each sleeping area. If your home contains fuel-burning appliances, fireplaces, or an attached garage, place detectors nearby according to the manufacturer’s instructions.
Pro Tip
- Avoid installing detectors directly next to cooking appliances, bathrooms, windows, doors, or HVAC vents, as these locations may increase the likelihood of nuisance alarms or interfere with accurate readings.
Carbon Monoxide Detector Maintenance Tips
To make sure your detector continues working properly, follow these maintenance recommendations:
Dos:
- Test your detector monthly using the test button.
- Replace removable batteries according to the manufacturer’s recommendations.
- Keep the detector free of dust and debris.
- Replace the entire unit when it reaches its end-of-life date.
- Follow the manufacturer’s maintenance and testing instructions.
Don’ts:
- Ignore low-battery or end-of-life warnings.
- Install detectors behind furniture or other obstructions.
- Paint over or cover detector vents.
- Remove batteries from detectors unless replacing them.
- Continue using a detector beyond its recommended lifespan.
What Can Cause Carbon Monoxide in a Home?
Carbon monoxide is produced whenever fuel burns. Common sources include:
- Gas furnaces and water heaters
- Gas stoves and ovens
- Fireplaces and wood stoves
- Portable generators
- Vehicle exhaust from attached garages
- Blocked chimneys or flues
- Malfunctioning fuel-burning appliances
Power outages can increase the risk of carbon monoxide exposure because homeowners often rely on alternative heating and power sources. As This Old House plumbing and heating expert Richard Trethewey adds, “As soon as the power goes out, what do people do? They’re going to light a fireplace.” Generators, kerosene heaters, fireplaces, and other fuel-burning devices can all produce carbon monoxide, making it especially important to have working detectors with battery backup during outages.
FAQs About Carbon Monoxide Detectors
What are the symptoms of carbon monoxide poisoning?
Symptoms of carbon monoxide poisoning can resemble the flu and may include headache, dizziness, weakness, nausea, confusion, and chest pain. If you or others in your home experience these symptoms, move to fresh air immediately and seek medical attention.
Am I supposed to test my carbon monoxide detector?
Yes, you should test your carbon monoxide detector at least once a month using the test button. The alarm should sound when tested, confirming that the detector is functioning properly.
Where should I put my carbon monoxide detectors?
Install carbon monoxide detectors on every level of your home and outside each sleeping area. For added protection, place detectors near fuel-burning appliances according to the manufacturer’s instructions.
How often should I replace a carbon monoxide detector?
Most carbon monoxide detectors need replacing every five to 10 years, depending on the model. Check the manufacturer’s recommendations and replace the unit when it reaches its end-of-life date.
Our Methodology
To provide our readers with the best product recommendations possible, we rely on several key sources of information to help guide our selection process.
- Initial research: Our research process began by generating a list of carbon monoxide detectors with a significant number of verified buyer reviews and an average customer review rating of 4–5 stars on Amazon. We looked at positive and negative reviews alike, focusing on information from both satisfied and critical buyers.
- Expert insights: Through years of experience, we’ve learned that listening to what others have to say is key to building accurate, well-rounded articles. To complement our in-house expertise, our team looked at reviews and videos from trusted publications and independent testers, spoke with subject matter experts, and drew insights from reader contributions.
- Final product selection: We then began fine-tuning our list by replacing older models with the latest versions and eliminating any discontinued models. From there, we pared the list down by comparing each model’s feature set and selecting the best-in-class options for a variety of buyers, budgets, and scenarios.
Why You Can Trust Us
This Old House has empowered homeowners and do-it-yourself (DIY) enthusiasts for more than four decades with top-notch home improvement advice in the form of television programs, print media, and digital content.
Our team focuses on creating in-depth product and service review content. To date, we’ve published over 1,600 reviews on products for the home, from doorbell cameras and dining room decor to circular saws and snow blowers.
Once we conclude the research and testing phases, we craft a comprehensive, user-friendly article of recommended products and additional information to help our readers make the right purchase.
