9 Best CO2 Monitors for Home Use (October 2026)
The best home CO2 monitors include the Aranet4 CO2 Monitor for simple CO2 tracking, the Airthings Wave Plus for CO2 and radon, and the GoveeLife H5140 CO2 Monitor for outlet-powered alerts.
On this page (5 sections)
The Aranet4 CO2 Monitor is the best CO2 monitor for most homes, thanks to its NDIR sensor, readable e-ink screen, optional buzzer and app history. Choose GoveeLife for outlet-powered alerts, or BREATHE if you want CO2 alongside particle and chemical readings.
A CO2 monitor helps you see how readings change as a room fills with people or gets fresh air. It measures one part of indoor air, so decide whether you need CO2 alone or want readings such as radon, particles or VOCs too.
For a plain overview of what these devices can tell you, read CO2 monitors for home use. Our guide to a good CO2 reading at home explains how to interpret the number.
Our picks at a glance
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How we chose home CO2 monitors
We compared the stated sensor methods, display information, power options, alerts, app features and extra readings against common home uses. Our score weighs specs and features against what you're shopping for.
A CO2 display is most useful when you can check it in the room you care about. Battery models can sit away from an outlet, while powered options suit a fixed location where continuous operation is the priority.
An app can add history or alerts, but it also brings setup and connection requirements. Check whether the specific feature you want works over Bluetooth, Wi-Fi or with a separate hub.
Compare the best CO2 monitors for home use
These monitors differ in power, app access and the readings they track alongside CO2. Use the table to narrow the field, then check the individual details below.
| Product | Best for | Power | Readings | App history | Our score |
|---|---|---|---|---|---|
| Aranet4 CO2 Monitor | simple CO2 tracking | 2 included AA batteries | CO2, temperature, relative humidity, atmospheric pressure | Up to 90 days | 8.8 |
| Airthings Wave Plus | CO2 and radon | 2 AA batteries | Radon, CO2, VOCs, humidity, temperature, air pressure | 8.5 | |
| GoveeLife H5140 CO2 Monitor | outlet-powered alerts | AC power | CO2, temperature, humidity, clock | 8.0 | |
| BREATHE Airmonitor Plus Gen 2 | multiple air readings | USB-C or rechargeable battery | CO2, particles, TVOC, HCHO, temperature, humidity | 7.9 | |
| Temtop M10+ CO2 Meter | long battery life | Battery powered | 7.7 | ||
| Airthings Wave Enhance | bedrooms and offices | 2 included AA batteries | CO2, VOCs, humidity, temperature, pressure, noise, light | 7.5 | |
| Handheld NDIR CO2 Meter | portable spot checks | Battery or optional 9V adapter | 7.1 | ||
| SwitchBot CO2 Monitor | a large display | Built-in battery, up to 12 months | 7.0 | ||
| 16-in-1 Air Quality Monitor with 7-Inch Screen | a broad at-a-glance display | Rechargeable with USB-C charging | 6.9 |
CO2 monitor picks by room and routine
The best choice depends on how you plan to use the reading: a quick glance, a long-term trend, or a wider view of indoor conditions. These nine picks are ordered by score.
1. Aranet4 CO2 Monitor: Best for simple CO2 tracking
Aranet4 CO2 Monitor: Best for simple CO2 tracking
- NDIR CO2 sensor
- E-ink display
- Battery life up to 4 years
- App history up to 90 days
A prominent CO2 number, color coding and optional buzzer make this a focused choice for tracking ventilation. Battery power and an app with historical graphs suit flexible placement.
Pros
- NDIR sensor
- E-ink display
- Optional buzzer
Cons
- No Wi-Fi feature specified
- Measures fewer air factors than multi-sensor picks
Aranet4 is the clearest fit if you mainly want to watch CO2 and decide when to ventilate. Its prominent CO2 number and color coding make the reading easy to check, and an optional buzzer can alert you when the concentration gets too high.
The e-ink display and battery operation give you flexibility to place it away from a cable. SAF states that battery life can reach 4 years, though actual life can depend on use.
The app shows real-time readings and up to 90 days of historical data in graphs. Temperature, relative humidity and atmospheric pressure round out the readings without turning this into a broad particle or VOC monitor.
Choose Aranet4 if a direct CO2 reading, clear display and simple placement matter most. If you want radon tracked in the same device, compare the Airthings Wave Plus below.
2. Airthings Wave Plus: Best for CO2 and radon
Airthings Wave Plus: Best for CO2 and radon
- Measures radon, CO2, VOCs, humidity, temperature and pressure
- Color-coded visual indication
- Bluetooth app
Wave Plus combines CO2 tracking with radon and other indoor readings. Pick it when those extra measurements are part of your goal, not just a larger metric count.
Pros
- Includes radon measurement
- Battery powered
- Bluetooth app and online dashboard
Cons
- Allow a 7-day sensor settling period
- CO2 is one of several readings
Wave Plus is the pick for a home where radon measurement matters alongside CO2. It also tracks VOCs, humidity, temperature and air pressure, so it covers several indoor factors in one battery-powered unit.
Wave in front of the device for a color-coded visual indication, or connect to the Airthings app by Bluetooth for detailed readings. The product description also includes an online dashboard with advanced analytics.
Airthings says the sensors need a 7-day settling period in a new environment. Plan for that before using its readings to make decisions, and review the device instructions for placement.
Choose Wave Plus if you want a combined radon and air quality monitor. For CO2-focused tracking without radon, the Aranet4 offers a more focused set of measurements.
3. GoveeLife H5140 CO2 Monitor: Best for outlet-powered alerts
GoveeLife H5140 CO2 Monitor: Best for outlet-powered alerts
- CO2, temperature, humidity and clock display
- Buzzer, app and email alerts
- App history up to 2 years
This powered monitor pairs a four-metric display with adjustable alerts and long app history. It suits a fixed spot where outlet power and app connection are practical.
Pros
- Three alert methods
- Up to 2 years of app history
- Voice queries through Alexa or Google Assistant
Cons
- Requires AC power
- Clock requires app connection
GoveeLife suits a fixed place where you want the monitor powered continuously from an outlet. Its display shows CO2, temperature, humidity and a clock, while its alert system can use a buzzer, app notifications and email reports.
You can set thresholds for CO2, temperature and humidity. App features include up to 2 years of historical data and CSV export, and CO2 readings can be queried by voice through Alexa or Google Assistant.
This model needs AC power, so it is less flexible to move than the battery-powered picks. Its clock also requires an app connection, and the product notes that the air purifier cannot be linked because it does not effectively reduce CO2.
Choose it if alerts and long app history are useful in a bedroom, nursery or office with a nearby outlet. For battery-powered tracking, compare Aranet4 or the Temtop M10+.
4. BREATHE Airmonitor Plus Gen 2: Best for multiple air readings
BREATHE Airmonitor Plus Gen 2: Best for multiple air readings
- Measures CO2, PM1, PM2.5, PM10, TVOC, HCHO, temperature and humidity
- NDIR CO2 measurement
- 90-day app history and export
BREATHE adds particle and chemical readings alongside CO2, with app graphs and export. Its battery supports short portable sessions, and USB-C power supports continuous use.
Pros
- Eight stated measurements
- Configurable CO2 and PM2.5 alerts
- Data export
Cons
- Portable battery use is up to 6 hours
- App connection uses 2.4 GHz Wi-Fi
BREATHE gives you a broader view than a CO2-only meter. It measures CO2, PM1, PM2.5, PM10, TVOC, formaldehyde, temperature and humidity, with app graphs, configurable CO2 and PM2.5 alerts, and data export.
Its NDIR CO2 measurement makes it a useful fit when you also want particle and chemical readings in the same device. The app connects over 2.4 GHz Wi-Fi and stores up to 90 days of data.
The rechargeable battery supports up to 6 hours of portable use, and the monitor can operate while connected to USB-C power. That makes it suitable for moving between rooms for shorter periods, while plugged-in use works for continuous monitoring.
Choose BREATHE if you want several types of indoor air readings and app history. If you only need a direct CO2 reading, a more focused monitor may be easier to place and interpret.
5. Temtop M10+ CO2 Meter: Best for long battery life
Temtop M10+ CO2 Meter: Best for long battery life
- Measures CO2, PM2.5, TVOCs, temperature and humidity
- E-ink display
- Battery life up to 60 days
The M10+ combines CO2 with particle and TVOC readings in a battery-powered device. Bluetooth and hourly logging suit nearby checks without relying on Wi-Fi.
Pros
- Up to 60 days of battery life
- Alarm can be muted
- Bluetooth app connection
Cons
- Bluetooth requires staying nearby for app access
- Does not measure radon or carbon monoxide
Temtop M10+ combines CO2 with PM2.5, TVOCs, temperature and humidity, using an e-ink display. The stated battery life of up to 60 days may suit a room where you want to leave the monitor in place between charges.
Its Bluetooth app supports real-time updates, calibration and historical data. Hourly data logging suits trend review, but you need to stay nearby for Bluetooth access rather than checking it from anywhere.
The alarm can be muted, which may help if you want bedroom monitoring without sound. Temtop says the device does not measure radon or carbon monoxide, so choose a separate device if either reading is needed.
Choose M10+ if you want several readings and long battery life with a nearby phone connection. For radon, compare it with Wave Plus instead.
6. Airthings Wave Enhance: Best for bedrooms and offices
Airthings Wave Enhance: Best for bedrooms and offices
- Measures CO2, VOCs, humidity, temperature and pressure
- Also tracks noise and light
- Battery powered
Wave Enhance adds noise and light tracking to its air readings, making it a fit for a bedroom or home office where room conditions matter. The full readings appear in the Bluetooth app.
Pros
- Tracks noise and light
- Battery powered
- App supports notifications and trend review
Cons
- Full readings are in the app
- No radon measurement specified
Wave Enhance adds noise and light readings to CO2, VOCs, humidity, temperature and air pressure. That combination suits a bedroom or home office where you want to see both air readings and other room conditions.
The unit is battery powered and connects to the Airthings app through Bluetooth. Its touch sensor gives a color-coded air quality indication, while the app provides current readings, notifications and trends.
Its measurements do not include radon, so it is not a substitute for a radon monitor. The app is also where you access the full reading set, which may matter if you prefer every value on the device itself.
Choose Wave Enhance when noise and light tracking help you understand your room. If radon belongs in the same monitoring setup, consider Wave Plus.
7. Handheld NDIR CO2 Meter: Best for portable spot checks
Handheld NDIR CO2 Meter: Best for portable spot checks
- NDIR CO2 sensor
- CO2 range of 0 to 9,999 ppm
- Measures temperature and humidity
A handle and battery power suit moving between rooms for spot checks. It also measures temperature and humidity, with a manual calibration feature.
Pros
- Portable handle design
- NDIR sensor
- Battery or adapter power
Cons
- 9V adapter is not included
- No app or historical data feature specified
The handheld meter is designed for moving between locations rather than leaving one screen on a table. It measures CO2 with an NDIR sensor and also reports temperature and humidity, with an audible alarm and manual calibration.
Its stated CO2 range runs from 0 to 9,999 ppm. It can run on batteries or a 9V adapter, but the adapter is not included.
This simple setup may appeal if you want to take readings in several rooms or bring the meter to a classroom or office. No app or history feature is specified, so it is a weaker fit if trend charts are important to you.
Choose it for portable spot checks and a direct display. For app graphs and long-term history, compare the Aranet4 or GoveeLife.
8. SwitchBot CO2 Monitor: Best for a large display
SwitchBot CO2 Monitor: Best for a large display
- 92 mm display
- CO2, temperature, humidity, time, date and comfort level
- Audible, visual and app alerts
The large screen shows several readings together, and the built-in battery supports flexible placement. App notifications require a SwitchBot Hub.
Pros
- Large display
- Wall mounting or adjustable bracket
- Built-in battery
Cons
- App alerts require a separate Hub
- Does not list an app history duration in the core features
SwitchBot puts CO2, temperature, humidity, time, date and comfort level on a 92 mm screen. Its built-in battery can last up to 12 months, and a bracket or wall mounting gives you a choice of placement.
The monitor offers audible and visual alerts, while app notifications require a SwitchBot Hub. Its stated CO2 range is 400 to 9,000 ppm, and it refreshes readings every second.
The screen and built-in battery make it a practical fit if you want several readings visible together without a cable. Check the Hub requirement before relying on phone alerts.
Choose SwitchBot if the screen size and flexible placement appeal to you. For a monitor with app history specified without a separate hub, compare GoveeLife or Aranet4.
9. 16-in-1 Air Quality Monitor with 7-Inch Screen: Best for a broad at-a-glance display
16-in-1 Air Quality Monitor with 7-Inch Screen: Best for a broad at-a-glance display
- Displays CO2, particles, HCHO, TVOC, temperature, humidity, AQI and time
- 7-inch display
- Up to 8 hours of runtime
Its large screen presents many readings at once, including CO2 and particle measurements. The stated 16-in-1 count combines nine detectable parameters with seven alert types.
Pros
- Large display
- Multiple readings and alert types
- Includes USB-C cable and AC adapter
Cons
- Up to 8 hours of runtime
- The 16-in-1 count includes alert types
This monitor has a 7-inch display for CO2, particles, HCHO, TVOC, temperature, humidity, AQI and time. Its “16-in-1” description combines nine detectable parameters with seven types of AQI alert buzzers.
The screen has three brightness settings, and the device offers up to 8 hours of runtime with USB-C charging. The included AC adapter also gives you a charging option at home.
This is a broad display choice if you prefer to see many readings without navigating menus. Its stated runtime is shorter than the battery claims for several other picks, so consider where you can charge it.
Choose it if you want a large screen with multiple indoor readings and alerts. For a more focused battery-powered CO2 monitor, the Aranet4 is a simpler alternative.
What matters when choosing a home CO2 monitor?
A good home CO2 monitor should measure the room you care about, show readings in a useful way and fit your power and connection needs. Start with those basics before deciding whether extra sensors are worth it.
Does the CO2 monitor use NDIR?
NDIR is a direct CO2 sensing method used by several picks here, including Aranet4, BREATHE and the handheld meter. Our guide to NDIR sensors in CO2 monitors explains the method and what to check when comparing devices.
Sensor method is one part of the decision. Consider the display, placement, alerts and whether the monitor measures the other factors you need.
Do you need an app or just a screen?
A screen gives you a local reading without opening your phone, while an app can add history, alerts or remote access. Aranet4 and GoveeLife offer app history, while the SwitchBot requires a Hub for app notifications.
Check the connection type before buying. Bluetooth generally means your phone needs to be nearby, while Wi-Fi can support app access away from the room when setup and network requirements are met.
Should you choose a CO2-only monitor or a multi-sensor device?
A CO2-focused monitor is easier to match to a ventilation question, while a multi-sensor device adds readings such as particles, VOCs, humidity or radon. Those extra numbers are helpful only if you plan to use them.
For a wider view of home monitors and the readings they cover, see our home air quality monitor guide. If you already have another air quality monitor, read how accurate home air quality monitors are before treating any single number as a complete picture.
Which power type fits the room?
Battery power helps when you want to move a monitor or place it away from an outlet. Plug-in models suit a fixed location where continuous power is more useful than portability.
Consider how often you'll check the screen and whether you need an app. A monitor that stays in a convenient spot is more useful than one with extra features you rarely access.
Which home CO2 monitor should you choose?
Pick the Aranet4 if your main goal is a clear CO2 reading with a buzzer option and long battery life. Choose GoveeLife if you want outlet-powered alerts and extended app history, or BREATHE if particles and chemical readings matter alongside CO2.
If radon is part of your decision, compare the Airthings Wave Plus with a dedicated radon monitor. Start with CO2 monitors for home use to match the readings to the question you want to answer.
Our top 3 picks at a glance
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Frequently asked questions
What should you look for in a home CO2 monitor?
Choose a monitor that measures CO2 directly, has a display you can read where you plan to place it, and uses a power source that fits that spot. An app, history, or alerts can help if you want to review patterns or check readings remotely.
For more than ventilation tracking, compare which extra readings matter to you.
Is an NDIR sensor useful in a CO2 monitor?
NDIR is a sensor method used to measure CO2 directly. Aranet4, BREATHE Airmonitor Plus Gen 2, and the handheld Gain Express meter specify NDIR measurement.
Learn what an NDIR sensor does before comparing models, since a long feature list does not by itself tell you how CO2 is measured.
Can an air purifier lower CO2?
A standard air purifier does not lower CO2. To reduce indoor CO2, bring in outdoor air through ventilation, such as opening windows when suitable or using an exhaust fan.
A monitor can show how readings change when you ventilate, but it does not remove CO2.
Where should you place a CO2 monitor?
Place the monitor in the room where you want to understand ventilation, in a spot where its display is easy to check and airflow is not blocked. Follow the device instructions for placement and sensor settling.
Avoid choosing a location based only on convenience if it gives you little information about the occupied part of the room.
