The best smoke detectors, tested and reviewed

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Like most modern households, we've filled our home with synthetic, petroleum-based materials, from our couch cushions to our daughter's toys. These everyday products make house fires burn faster than ever, says Susan McKelvey of the National Fire Protection Association (NFPA). She says that I may have as little as one to two minutes to get my family out once a smoke alarm sounds. With such a narrow window, one of the best smoke detectors is non-negotiable for my family's safety. The best smoke alarm strikes a delicate balance between sensitivity and reliability, giving us precious time to escape in the case of a fire without triggering false alarms every time I cook. Some models also detect carbon monoxide, a deadly, odorless gas.

After consulting with three fire safety experts — including McKelvey, Brian Sayles, fire marshal at Lane Fire Authority, and Nicole Sanders, public education lead at UL Research Institute's Fire Safety Research Institute — I tested 10 of the top smoke alarms across three brands for ease of installation and setup, reliability, accessibility features, and safety compliance. The First Alert SM300-AC is my top pick for its dependable dual sensors, battery backup, and whole-home interconnect capability. For those looking for smart features, I recommend the First Alert SC5, a smoke and carbon monoxide detector that combines smartphone alerts with exceptionally broad interconnect compatibility, including with the discontinued Google Nest Protect system.

Learn more about how Business Insider Reviews tests and researches home products.

Our picks for the best smoke detectors

Best overall: First Alert SM300-AC - See at Amazon

Best smoke and carbon monoxide detector: First Alert SMCO100V-AC Interconnect - See at Amazon

Best budget: First Alert SMI100-AC - See at Amazon

Best smart: First Alert SC5 - See at Amazon

Best battery: First Alert SMCO500V - See at Lowe's

Our top picks, compared

Best overall

It performed consistently in my testing and meets expert safety recommendations. I tested the First Alert SM300-AC multiple times with aerosol smoke, and it alarmed effectively and consistently every time. Its expert-recommended combination of hardwired connectivity, replaceable battery backup, interconnect capability, and dual sensors — features Sayles recommends and prioritizes for his own home — set it apart from the competition. It's hardwired, but the battery backup means you'll never be without an alarm, even during a power outage.

The dual sensors provide broad protection without false alarms. This alarm features ionization sensors for fast-flaming fires and photoelectric sensors for slow-smoldering fires — a rare feature among alarms that also offer hardwiring, battery backup, and interconnectivity. "I use dual-sensor alarms to provide the earliest possible detection in my own home," Sayles says. During my testing in real-world cooking and steam conditions, it never triggered a false alarm, which is why this is also my pick for the best dual-sensor smoke alarm. Most alarms that meet the critical safety features recommended in this guide rely on a single sensor type, making this a genuinely rare and highly recommended buy.

Interconnectivity is a lifesaving feature. "I generally recommend hardwired, interconnected smoke detectors whenever possible," Sayles says. This model can connect with almost a dozen other compatible First Alert alarms to form an interconnected network, including three other alarms featured in this guide (our best smoke and carbon monoxide, best budget, and best smart picks). However, in an interconnected system, knowing which alarm triggered first is critical for homeowners and first responders. This alarm features a latching indicator, alerting you to the origin of the alert — after I silenced the alarm, the unit continued to flash a red LED light.

Best budget

For the price, you're getting critical safety features that matter most. The First Alert SMI100-AC delivers hardwired power and interconnect technology at a budget-friendly price point — two of the most important features to look for in a smoke detector. Once hardwired, it automatically connects to other compatible First Alert units, including my best overall, smoke and carbon monoxide, and smart smoke detector picks. The interconnectivity with other units means you can strategically mix and match price points throughout your home without sacrificing an interconnected safety network.

I appreciate the straightforward installation and maintenance reminders. Without application connectivity or voice alerts, this is a true set-it-and-go option. The test button is clearly marked and responsive, which is important for the twice-yearly testing that Sanders recommends. The device untwists easily for dusting, and similar to my best smoke and carbon monoxide detector pick, a green LED flashes when cleaning is needed. The 9-volt battery backup (included) slides into a locking drawer, and the unit chirps for low battery, malfunction, or end-of-life alerts. While a flashing red light indicates normal operation, I would have preferred green for normal operation and red for the cleaning alert.

The single-ionization sensor and the less urgent-sounding alarm are this model's biggest flaws. Unlike our top pick's dual sensors, this alarm uses only ionization detection, which responds better to fast-flaming fires but may be slower to detect smoldering fires. While the alarm meets NFPA's code requirement of 85 decibels at 10 feet, it wasn't as loud as higher-end models and I perceived lower urgency in its tone. It does not detect carbon monoxide.

Best smoke and carbon monoxide detector

It combines the best smoke and carbon monoxide detection with interconnectivity. When the First Alert SMCO100V-AC is triggered, it beeps and verbally tells you whether it detected smoke or carbon monoxide and from which room. It's also hardwired with a replaceable 9-volt battery backup and connects with nearly a dozen compatible First Alert alarms to form an interconnected network, including three other detectors featured in this guide (our best overall, best budget, and best smart picks). This standout combination of features is why this alarm is also my pick for the best interconnected smoke detector.

The alarm pairs an urgent tone with clear voice alerts to eliminate confusion in emergencies. "Combination units can be effective, but they often cause confusion," Sayles says. Rather than leaving you to interpret a beep pattern in a panic, this alarm tells you exactly what's wrong and where: "Warning, evacuate, smoke in [room name], evacuate." The carbon monoxide alert was just as specific and also reported the highest level detected. The smoke alarm itself features a sharp, attention-grabbing beep that sounds more like an emergency broadcast alert rather than a low battery chirp. It's loud and urgent, matching the alarm intensity of my battery-powered pick while outperforming my best overall, budget, and smart picks.

There's a few trade-offs, but they aren't deal breakers for my family. This alarm features photoelectric sensors, which excel at detecting smoldering fires like electrical shorts inside walls or embers falling onto fabric. While it was consistently sensitive to aerosol smoke without false alarms in testing, it could be slower to detect high-heat fires that produce little to no smoke, such as kitchen grease fires. Additionally, the green LED that flashes when cleaning is needed helps you keep sensors clear of dust, but without consulting the manual, is easily misinterpreted as normal operation. These trade-offs are minor compared to the alarm's overall performance and features, and pairing this photoelectric alarm with an ionization model in high-risk areas like the kitchen delivers the earliest possible detection across all fire types.

Best smart

Remote alerts give me peace of mind when I'm not home and serve as a critical accessibility feature. The First Alert SC5 sends notifications to my phone via app and email the moment it detects smoke or carbon monoxide. With pets and a baby at home, getting an instant alert means I can call 911 or check in immediately, no matter where I am. I would also consider this alarm system if I were a caretaker for an elderly or disabled loved one, or if I had a vacation home or rental property to monitor. However, this feature isn't just about being informed while away — it's also transformative for people with hearing impairments, deep sleepers, or anyone who uses headphones or earbuds throughout the day. A visual phone notification can reach you when a traditional alarm might not.

It's easy to set up and features broad interconnect compatibility. This model replaces the discontinued Google Nest Protect smart detectors and can connect with almost a dozen other compatible First Alert smoke detectors, including our best overall, best smoke and carbon monoxide, and best budget picks. I have Google Nest Protect units installed in my home, and this First Alert communicated seamlessly with them and other compatible First Alert systems. Setup took just 5 minutes — I downloaded the First Alert by Resideo app, scanned the QR code on the back of the device, and it was connected.

It has clear voice alerts with helpful context. While the alarm isn't as loud or urgent-sounding as my top pick for smoke and carbon monoxide, it's distinctly different and more urgent than a low-battery beep. When it alarms, it announces "Emergency, smoke detected in the [room name]" — immediately telling me where the problem is. It also announces the highest level of carbon monoxide detected. When I silenced the unit, it verbally confirmed the command while continuing to flash red. Once the air was clear, it announced "alarm is over" and switched to a blinking green light every 40 seconds.

This is a replacement for, not a replica of, the Google Nest Protect. If you're coming from Google Nest Protect and loved its features like the lighted pathway, which acts as a nightlight during normal use and illuminates an exit route during an emergency, or Nest app compatibility, this First Alert won't replicate that experience. At the current $129 price point, users expecting a Nest Protect replica may find this model doesn't offer the same premium user experience.

Best battery

This smoke detector stands out from other battery-powered models thanks to its interconnectivity. When hardwiring isn't feasible, the best battery-powered option for homes is the First Alert SMCO500V, featuring wireless interconnect capabilities and replaceable batteries. While many battery-powered smoke detectors work in isolation, this one connects wirelessly with compatible alarms throughout your home. When one detected smoke, all alarms sounded simultaneously. It also provided clear voice alerts that specify the fire location.

Replaceable batteries offer ease of maintenance but are easier to disable. Sayles recommends replaceable battery backup over sealed 10-year batteries because you can replace the batteries immediately if they fail early, rather than dealing with warranty claims or replacing the entire unit. However, removable batteries make it easier for frustrated users to disconnect alarms and may forget to restore power — a risk that's especially relevant with this model because it was the most sensitive to aerosol smoke in my testing. While I didn't experience any nuisance alarms when following my local code requirements for placement, improper placement too close to stoves or bathrooms could lead to frequent false alarms.

The clear voice alerts and effective alarms gave me confidence that this would wake my family. The alarm is loud and attention-grabbing — comparable to my best smoke and carbon monoxide pick and noticeably louder than our budget and smart picks. But it's not just about volume — the best smoke detector sounds urgent too. The beep sounds more like an emergency broadcast system than a typical smoke alarm, which sets it apart from non-urgent alarms. Once programmed, it announces the specific location: "Warning, evacuate, smoke in [room name], evacuate." After silencing during testing, it announces "alarm has been silenced" and continues flashing a red light as a visual reminder until the smoke clears.

However, it has a photoelectric sensor only and limited interconnectivity compatibility. This alarm uses photoelectric detection only, which may be slower to detect fast-flaming fires. While it connects to other compatible First Alert units, compatibility is limited, with First Alert SM500V being the only option for a wireless, battery-powered interconnected safety network.

If you prefer a sealed 10-year battery unit, I recommend the First Alert SM310, which also performed well in testing and has the advantage of dual sensors, but does not have interconnectivity compatibility.

What to look for in the best smoke detectors

When shopping for the best smoke detector, it's critical not to skimp on the most important features. "We estimate that 50 years ago, you had about 17 minutes to escape from a home fire while today that time could be just three minutes or less from the time the fire starts," Sanders says. This dramatic reduction is due to the more synthetic materials in our homes and changes in how we build them. "Wall linings, windows and interior doors fail more quickly. Floors collapse more quickly," she says. For the best protection against today's faster-burning fires, consider these features:

Certifications and safety standards: UL Standard 217, 8th Edition or later is the current safety standard for smoke alarms and should be clearly marked on the detector packaging, on the alarm itself, and in the instruction manual. "UL certification means the product has been independently tested and verified to perform as the manufacturer claims under specific conditions. Unlisted or improperly certified products may fail to detect smoke, respond too slowly, or malfunction altogether," Sayles says. Building codes generally require smoke detectors to be certified by a nationally recognized testing laboratory, such as UL (Underwriters Laboratories) or ETL (Intertek).

Based on my research, I am currently not recommending smoke detectors from Kidde, Siterwell, or X-sense, as I've found a record of defective products, recalls, and/or lapses in safety certification.

Sensor type: The best smoke detector uses ionization and photoelectric sensors. Ionization sensors respond faster to fast-flaming fires, like a grease fire on the stove or burning newspaper, which produce intense heat and flames but relatively little smoke. Photoelectric sensors are more responsive to smoldering fires, like an ember catching a curtain or an electrical fault, which produce large amounts of smoke before ever creating a flame. "You cannot predict the type of fire you may have or when it will occur," McKelvey As a result, NFPA recommends buying combination smoke alarms, which feature both ionization and photoelectric technologies in a single device," she says.

Power source: The best smoke detector for a home is hardwired with battery backup. "Working batteries are essential for these alarms because they ensure that the smoke alarms will operate in a fire even if the home loses power," McKelvey says.

If battery-only is your only option, Sayles recommends replaceable battery units over sealed 10-year units. While sealed batteries may seem convenient, they can fail unpredictably. Smoke detectors have manufacturing dates, but most homeowners either can't or don't check them at the time of purchase. "You don't know how long that alarm sat on a shelf before purchase. If the battery fails early, the entire unit becomes useless," Sayles explains. Replaceable batteries allow you to correct a failure immediately rather than replacing the whole device.

Interconnectivity: The best smoke detector communicates with other alarms throughout your home. "Interconnected smoke alarms — whether wireless or hard-wired — are designed so that when one alarm sounds, they all do," McKelvey says. Sayles says that this feature significantly improves early warning and escape time by giving everyone in the house — no matter where they are — critical extra seconds to escape. This is a life-saving advantage in multi-story homes or layouts where bedrooms are far from main living areas.

A latching indicator continues to flash a red LED light even after an alarm is silenced, identifying the exact origin of the alert for both homeowners and first responders. This is critical in an interconnected system where multiple alarms are sounding, and all the interconnected alarms I recommend in this guide include this feature.

Accessibility and alert features: "Strobe lights, low-frequency alarms, and interconnected systems are critical for residents with hearing impairments. For older adults or those with limited mobility, early detection is everything — alarms must activate quickly and throughout the home," Sayles says.

We prioritized alarms with voice alerts that specify alarm type and location, instant remote smartphone notifications for accessibility, and decibel ratings high enough to wake heavy sleepers. While we tested two alarms with low-frequency alerts specifically designed for people who are hard of hearing, they didn't make our final recommendations due to a lack of features or design issues.

According to NFPA standards, smoke alarms must measure at least 85 decibels at 10 feet to meet code requirements. You can verify a model's decibel rating on the product page or in its manual.

Multifunctionality: Combination smoke and carbon monoxide detectors can be effective, but according to Sayles, they can also cause confusion. "Different beep patterns, lights, and alerts can be misinterpreted by homeowners, especially years after installation," he says. To help users avoid confusion, the combination smoke and carbon monoxide detectors I've recommended in this guide all feature voice alerts.

Installation: Hardwired units require basic electrical knowledge, including shutting off power at the breaker and testing wires with a voltage tester before connecting the unit's wiring. Battery-powered detectors don't require any electrical work but still need to be securely mounted to walls or ceilings, often using drywall anchors. For our testing, we prioritized models that included all necessary mounting hardware and clear instructions.

Many local fire departments offer free smoke alarm installation and inspection services. You can contact your local fire department to ask about available programs in your area.

Maintenance: At a minimum, all smoke detectors should have an easily accessible test button, and battery-powered models should clearly indicate when batteries are low, whether through a chirping sound, flashing light, or both. Smoke detectors should be cleaned of dust with a vacuum or compressed air spray once a month, tested when first installed and twice a year thereafter using both the test button and aerosol smoke, and batteries should be replaced as needed (typically every 6 months to 2 years depending on battery type). The entire unit should be replaced every 10 years, or sooner if a sealed battery dies or if the alarm fails to activate during testing.

How we test the best smoke detectors

I used insights from fire safety experts to develop an objective testing methodology with a point-scoring system to rank each of the 9 smoke detectors. I also circled back to Sayles with questions about my aerosol smoke testing methodology and outcomes to ensure my approach and conclusions were valid.

Certifications and safety standards: Before I began hands-on testing, I verified that each smoke detector featured clear certification markings from recognized testing laboratories such as UL or ETL. I checked device packaging, the device itself, and instruction manuals for certifications and safety standards.

Ease of installation and setup: I timed how long each detector took to install and noted whether instructions were clear, if all mounting hardware was included, and whether additional tools were needed.

Alarm reliability (smoke detection): For each detector, I used CRC Aerosol Smoke Test following a consistent protocol: I applied two three-second bursts of aerosol smoke directed toward the detector, with approximately two seconds between sprays. I began testing at a distance of 36 inches and progressively moved closer — to 24 inches, 12 inches, 6 inches, and finally 3 inches — until the alarm activated. I waited at least 10 seconds between distances to allow the smoke to disperse and reach the sensor. This test was repeated a minimum of three times per detector, with up to 12 hours between test cycles.

For each trial, I recorded:

• Distance at which the alarm activated
• Time from first spray to alarm activation
• Consistency of activation across all three trials
• Whether the hush/silence feature worked effectively

Detectors that consistently activated at greater distances across multiple trials scored highest. Any detector that failed to activate by 3 inches across all trials was disqualified from further consideration.

Alarm volume and clarity: I triggered each alarm and measured the decibel level using a sound meter application on my phone. I also evaluated the perceived urgency of the tone and clarity of voice alerts from inside the room, outside the room, and one floor away.

Accessibility features: I scored each detector based on the number of accessibility features it included, such as voice alerts, low-frequency alarms, visual strobe lights, and smartphone notifications. For detectors with those features, I then assessed their functionality. For example, I evaluated whether voice instructions were location-specific and easy to understand, and observed visual indicators during both alarm and non-alarm states, noting brightness and visibility in daylight and low light from different angles. Detectors with more accessibility features scored the highest in my tests.

Sensitivity and false alarm resistance: According to Sanders, nuisance alarms or false alarms are most often related to cooking or bathroom steam. To evaluate false alarm resistance, I followed my local fire code requirements for smoke alarm placement and conducted two key tests:

• Steam test: Portland codes recommend that detectors not be placed within 3 feet of a bathroom, so I ran a hot shower with the bathroom door open and placed each detector 4 feet from the door. I monitored for activation over a 5-minute period.

• Cooking vapor test: Portland code requires detectors to be no less than 10 feet from a cooking device but no more than 20 feet, so I boiled water on the stove with each detector placed 12 feet away. I monitored for activation over a 5-minute period.

Interconnectivity: I triggered one alarm in each interconnected system and verified whether all connected units activated, measuring any delay between alarms. For detectors with location-specific voice alerts, I confirmed whether voice alerts correctly identified the originating room. I also tested whether silencing one unit silenced all interconnected units.

Maintenance and testing: I evaluated how easy it was to manually test each alarm using the test button, clean vents or sensors per manufacturer instructions, identify the manufacturing date and expiration information, and replace batteries when applicable.

Best smoke detector FAQs

Why do we only recommend First Alert smoke detectors?

I researched and tested smoke detectors from multiple brands, but First Alert consistently outperformed the competition across my testing criteria. Some brands didn't make it past the research phase due to a history of defective products, recalls, or lapses in safety certification. Others failed to pass or were significantly outperformed by First Alert models in hands-on testing for effectiveness, durability, features, and overall performance.

Should my smoke detector have a CO detector?

Combination smoke and carbon monoxide detectors offer important protection, as carbon monoxide is a deadly, odorless, and colorless gas. However, Sayles says combination units can cause confusion if alerts for carbon monoxide and smoke are not clearly and easily distinguished from each other. My pick for the best combination smoke and carbon monoxide detector, the First Alert SMCO100V-AC Interconnect, features voice alerts that clearly distinguish between smoke and carbon monoxide alerts.

What's the best smoke detector for people who are hard of hearing?

According to the NFPA, smoke detectors with low-frequency alarms at 520 Hz are most effective in waking individuals who are hard of hearing. While we tested two alarms with low-frequency features, neither met our overall quality and performance standards for recommendation. I recommend the First Alert SC5 as the most accessible option in our roundup. Its smartphone and email notifications provide visual alerts that can supplement auditory alarms. For help identifying specialized low-frequency smoke alarms or alerting devices for your specific needs, contact your local fire department.

What is the best smoke detector for a house?

Sayles recommends hardwired, dual-sensor alarms with replaceable batteries and interconnect capabilities. Our best overall pick, the First Alert SM300-AC, combines all of Sayles' recommended features — hardwired power with battery backup, dual sensors, and interconnect capability — making it the most comprehensive safety solution for most homes. However, even the best smoke detector with the most advanced safety features will not protect you in an emergency if it is not properly installed, maintained, and replaced on time.

Do smoke detectors need to be cleaned?

Yes, use compressed air or a vacuum to remove dust from smoke detectors monthly.

Are hardwired or battery smoke detectors better?

Hardwired smoke detectors with replaceable battery backup are the gold standard, according to Sayles. This combination ensures your alarm will never be without power, and the batteries can be replaced without tossing the entire unit before its 10-year lifespan.

What's the best smoke detector for a kitchen?

Many smoke detectors are suitable for the kitchen, as proper placement is the single most important factor in preventing false alarms. "Smoke alarms should be installed at least 10 feet away from cooking appliances to help prevent those alarms," Sanders says. However, if your smoke detector is nearing its 10-year replacement date and you've struggled with frequent nuisance alarms despite proper placement, newer, dual-sensor technology may help. "New technology can better distinguish between smoke from a fire and steam from cooking. It may be worth investing in these new smoke alarms to ensure you don't disable them and forget to plug them back in," Sanders says.

What smoke detector do firefighters recommend?

As a fire marshal with over two decades of experience in fire service, Sayles chooses hardwired, dual-sensor alarms with replaceable batteries and interconnect capabilities to protect his own home. When purchasing any smoke alarm, Sayles says to do your due diligence. "Purchase UL-listed alarms, understand the features, confirm compatibility if alarms are interconnected, and follow manufacturer guidance. The 'best' alarm is the one that is properly installed, maintained, and replaced on time," he says.

What's the lifespan of a smoke detector?

"Smoke alarms should be replaced according to the manufacturer's recommendations, which is usually every 10 years, or when they stop working—whichever comes first," Sanders says. "If your smoke alarm is more than 10 years old, install new alarms and look for products that are third-party listed or certified."

How often should I test my smoke detectors?

"We recommend people test their smoke alarms twice per year, at minimum," Sanders says. Start by pressing the test button to confirm the horn works and the unit has power — but smoke detector testing doesn't end there. "Pressing the test button only confirms the horn works — it does not verify that the sensor can still detect smoke," Sayles says.

For thorough testing, Sayles recommends using aerosol smoke products designed specifically for smoke alarm testing, both for new installations and routine bi-annual checks. "To use them correctly, homeowners should follow the manufacturer's instructions, spray the test aerosol near (not directly into) the alarm, and confirm that the alarm activates promptly. A proper response means the alarm sounds within seconds and resets normally afterward. If it does not activate or behaves erratically, the detector should be replaced," he says.