Smart smoke detectors do what traditional alarms can't: tell you exactly where the danger is, alert you on your phone when you're away, and distinguish between a real fire and burnt toast. When seconds matter, smart alerts and voice announcements can mean the difference between a minor scare and a tragedy.
After evaluating the top smart smoke and carbon monoxide detectors for reliability, smart features, and ease of use, we've identified the best options for protecting your home in 2025. Here's everything you need to know.
Quick Picks: Best Smart Smoke Detectors at a Glance
| Category | Product | Price | Best For |
|---|---|---|---|
| Best Overall | Google Nest Protect (2nd Gen) | $119 | Best all-around smart smoke detector |
| Best Value | First Alert Onelink | $99 | Apple HomeKit integration, solid features |
| Best Budget | X-Sense Smart Smoke Detector | $39 | Affordable smart alerts |
| Best for Alexa | First Alert Onelink | $99 | Deep Alexa integration |
| Best for Google Home | Google Nest Protect | $119 | Native Google ecosystem |
| Best Hardwired | Kidde Smart Detect | $79 | Replaces existing hardwired units |
| Best Battery Life | Google Nest Protect (Battery) | $119 | 10-year sealed battery |
| Best Multi-Sensor | First Alert Onelink Environment Monitor | $119 | Smoke + CO + temp + humidity |
Best Smart Smoke Detectors: Detailed Reviews
Best Overall: Google Nest Protect (2nd Gen) – $119
Why it wins: The Nest Protect sets the standard for smart smoke detection. It speaks to tell you exactly what's wrong and where, sends phone alerts when you're away, tests itself automatically, and serves as a pathway light at night. Its Split-Spectrum Sensor detects both fast-burning and smoldering fires while minimizing false alarms.
Key Features:
- Split-Spectrum Sensor detects fast and slow-burning fires
- Electrochemical carbon monoxide sensor
- Voice alerts tell you the type and location of danger
- Phone notifications when you're away from home
- Heads-Up warning before full alarm (for cooking smoke)
- Pathlight: motion-activated nightlight
- App Silence: quiet false alarms from your phone
- Automatic monthly self-testing (no 3 AM chirps)
- Works with Google Home, Alexa, and other smart devices
Interconnect Feature: Multiple Nest Protects communicate wirelessly. If one detects smoke in the basement, all units announce the location throughout the house.
Best for: Most smart homes, Google ecosystem users, anyone who wants the most reliable and feature-rich smart smoke detector.
Available in: Wired ($119) and Battery ($119) versions. Both offer identical features.
Best Value: First Alert Onelink – $99
Why it wins: The First Alert Onelink delivers most of what makes Nest Protect great at a $20 lower price. It's one of the few smart smoke detectors with native Apple HomeKit support, making it ideal for iPhone users. Voice alerts, phone notifications, and interconnection are all included.
Key Features:
- Photoelectric smoke sensor + electrochemical CO sensor
- Voice alerts announce danger location
- Works with Apple HomeKit, Alexa, and Google Assistant
- Phone notifications for alerts and low battery
- Wireless interconnection with other Onelink detectors
- App Silence for nuisance alarms
- 10-year sealed battery (battery version)
- Hardwired version available for existing wiring
HomeKit Benefits: Triggers HomeKit automations—turn on all lights during an alarm, unlock doors for evacuation, or send alerts through HomePod speakers.
Best for: Apple HomeKit users, budget-conscious buyers who want premium features, Alexa households.
Best Budget: X-Sense Smart Smoke Detector – $39
Why it wins: Smart smoke detection doesn't have to cost $100+. The X-Sense Smart Detector offers phone notifications, app control, and self-testing at a third of the price. It's proof that safety features are becoming accessible at every budget.
Key Features:
- Photoelectric smoke sensor
- WiFi-connected with phone app
- Push notifications for alarms and low battery
- App Silence for nuisance alarms
- Self-testing with app notifications
- Replaceable battery (5-year sensor life)
- Works with Alexa and Google Assistant
- Multiple detector interconnection via app
Best for: Budget-conscious buyers, renters, secondary properties, anyone upgrading from basic detectors.
Trade-offs: No carbon monoxide detection (smoke only). No voice announcements (beep only). Build quality not as premium as Nest/Onelink.
Best for Alexa: First Alert Onelink – $99
Why it wins: The Onelink's Alexa integration goes beyond basic notifications. It works with Alexa Routines, announces alerts through Echo speakers, and can trigger other smart home actions when smoke or CO is detected.
Alexa Integration Features:
- Announces alerts on all Echo devices in your home
- Check status by asking “Alexa, is there smoke in the house?”
- Triggers Alexa Routines for automation (lights on, doors unlocked)
- Silence alarms by voice: “Alexa, silence smoke alarm”
- Low battery notifications through Alexa
Best for: Alexa-centric smart homes, anyone who wants voice control over smoke detector functions.
Best for Google Home: Google Nest Protect – $119
Why it wins: As a Google product, Nest Protect integrates seamlessly with Google Home. It announces alerts on Nest speakers and displays, shows status in the Google Home app, and triggers automations through Google Routines.
Google Home Integration:
- Announces alerts on Nest speakers and displays
- Check status: “Hey Google, is there smoke in the house?”
- Shows real-time status in Google Home app
- Works with Google Routines for automation
- Unified management with other Nest devices
- History of alerts and tests in Nest app
Best for: Google Home/Nest ecosystem users, anyone with Nest thermostats, cameras, or speakers.
Best Hardwired: Kidde Smart Detect – $79
Why it wins: Many homes have existing hardwired smoke detectors connected together. The Kidde Smart Detect replaces these units while adding smart features—no new wiring required. It's the easiest upgrade path for homes with hardwired interconnected systems.
Key Features:
- Replaces existing hardwired smoke detectors
- Uses existing interconnect wiring (all alarms trigger together)
- WiFi connectivity for phone notifications
- Smoke and carbon monoxide detection
- Voice alerts announce hazard location
- Works with Alexa and Google Assistant
- Battery backup during power outages
- Self-testing with app notifications
Best for: Homes with existing hardwired smoke detector systems, anyone replacing old interconnected detectors.
Note: If you have non-smart hardwired detectors, you can replace one with Kidde Smart Detect while leaving others—they'll still trigger together via the existing wiring.
Best Battery Life: Google Nest Protect (Battery) – $119
Why it wins: The battery-powered Nest Protect uses long-life lithium batteries that last up to 5 years and are user-replaceable. For the ultimate convenience, some users prefer this over worrying about wiring.
Battery Features:
- 6 AA lithium batteries (included)
- Up to 5-year battery life
- Low battery alerts via app (weeks before beeping starts)
- No wiring required—install anywhere
- Identical features to wired version
- Easy to relocate if needed
Best for: Rentals, homes without existing detector wiring, anyone who prefers battery-powered simplicity.
Best Multi-Sensor: First Alert Onelink Environment Monitor – $119
Why it wins: The Environment Monitor combines smoke and CO detection with temperature and humidity monitoring. It alerts you to conditions that could indicate problems—frozen pipes, excessive heat, or humidity that promotes mold growth.
Key Features:
- Smoke detection (photoelectric)
- Carbon monoxide detection (electrochemical)
- Temperature monitoring with high/low alerts
- Humidity monitoring with mold risk alerts
- Apple HomeKit, Alexa, and Google Assistant
- Voice alerts for smoke/CO
- Historical data in app
- Hardwired with battery backup
Best for: Vacation homes, basements, attics, anywhere environmental monitoring adds value beyond just fire detection.
Smart Smoke Detector Buying Guide
Sensor Types: Understanding Detection Technology
Different fires produce different types of smoke. The best protection uses multiple sensor types:
Photoelectric Sensors
- Best at detecting slow, smoldering fires (furniture, bedding)
- Less prone to false alarms from cooking
- Uses light beam disruption to detect smoke particles
Ionization Sensors
- Best at detecting fast, flaming fires
- More prone to nuisance alarms from cooking
- Uses radioactive material to detect smoke particles
Split-Spectrum Sensors (Nest Protect)
- Combines multiple wavelengths of light
- Detects both fast and slow fires
- Best at distinguishing real fires from nuisance smoke
Carbon Monoxide Sensors
- Electrochemical sensors detect CO gas
- Essential if you have gas appliances, attached garage, or fireplace
- CO is odorless and deadly—detection is critical
Recommendation: Choose detectors with both smoke AND carbon monoxide detection. Combo units ensure comprehensive protection.
Wired vs Battery: Which Should You Choose?
| Feature | Hardwired | Battery-Powered |
|---|---|---|
| Power source | Home electrical + battery backup | Batteries only |
| Installation | Requires wiring knowledge or electrician | DIY—mount and go |
| Reliability | Always powered (with backup) | Dependent on battery life |
| Interconnection | Wired + wireless | Wireless only |
| Best for | New construction, existing wired systems | Rentals, retrofits, easy installation |
Code requirements: Check local codes. Many jurisdictions require hardwired, interconnected detectors in new construction or major renovations.
Where to Install Smoke Detectors
Proper placement is critical for early detection:
- Every bedroom: Inside each sleeping area
- Outside sleeping areas: In hallways near bedrooms
- Every level: Including basement and attic
- Kitchen: At least 10 feet from cooking appliances
- Living areas: Family room, living room
- Garage: CO detector required if attached to home
Mounting tips:
- Ceiling mount is ideal (smoke rises)
- If wall-mounted, install 4-12 inches from ceiling
- Avoid areas with drafts, humidity, or temperature extremes
- Keep away from windows, doors, and HVAC vents
Smart Features Worth Having
Essential smart features:
- Phone notifications: Alert when you're away from home
- Voice announcements: Know exactly what and where the danger is
- App silence: Stop nuisance alarms without climbing a ladder
- Wireless interconnection: All detectors alarm together
- Self-testing: No more 3 AM low-battery chirps
Nice-to-have features:
- Pathlight: Motion-activated nightlight (Nest Protect)
- Heads-up warning: Alert before full alarm for minor smoke
- Smart home integration: Trigger lights, unlock doors during emergencies
- History/logging: Track when alarms occurred
Frequently Asked Questions
How often should I replace smoke detectors?
Replace smoke detectors every 10 years, regardless of whether they still work. Sensors degrade over time. Carbon monoxide detectors should be replaced every 5-7 years. Check the manufacture date on the back of your detectors.
Do smart smoke detectors work without WiFi?
Yes. Smart smoke detectors function as regular smoke detectors without WiFi—they'll sound the alarm locally. You lose phone notifications, app silence, and remote monitoring, but the core safety function works independently of your internet connection.
Can smart smoke detectors reduce false alarms?
Yes. Smart detectors with “heads-up” features (like Nest Protect) give a gentle warning before full alarm, allowing you to ventilate cooking smoke. App Silence lets you stop nuisance alarms instantly instead of fanning the detector. Split-spectrum sensors are better at distinguishing real fires from cooking smoke.
Should I get smoke-only or combo smoke/CO detectors?
If you have any gas appliances (furnace, water heater, stove), attached garage, fireplace, or generator, you need CO detection. Combo units are the most practical choice for most homes. CO detectors are also required by code in many jurisdictions.
Are smart smoke detectors worth the extra cost?
Smart features provide real safety benefits: phone notifications when you're away could save your home or pets, voice announcements help you respond faster, and app silence reduces the temptation to disable annoying detectors (a dangerous habit). For the 10-year lifespan of a detector, the $20-70 premium over basic models is worth it.
Final Verdict: Which Smart Smoke Detector Should You Buy?
For most homes: The Google Nest Protect ($119) offers the best combination of reliability, smart features, and peace of mind. Its voice announcements and heads-up warnings are genuinely useful.
For Apple HomeKit users: The First Alert Onelink ($99) provides excellent features with native HomeKit integration at a lower price.
On a budget: The X-Sense Smart Smoke Detector ($39) proves smart alerts don't require a premium price.
For existing hardwired systems: The Kidde Smart Detect ($79) adds smart features to your existing interconnected setup.
Smart smoke detectors turn a passive safety device into an active protector. They tell you what's wrong, where it's happening, and alert you even when you're not home. In an emergency, that information is invaluable.
Ready to upgrade your home's fire safety? Install smart smoke detectors and gain peace of mind knowing your home is protected—whether you're there or not.
