I bought the Airthings View Plus in August 2026. Six months later, I have a graph showing my bedroom CO2 hit 1,800 ppm on a night I kept the windows shut. That number shocked me. It is not normal. And it changed how I ventilate my house.
This is not a spec sheet review. I will tell you what the View Plus actually caught, what it missed, and whether the $249 price tag made sense for my home. If you are considering a smart air quality monitor, you need to know what data matters and what is just noise.
Why I Bought an Air Quality Monitor in the First Place
I live in a 1960s ranch house in the Pacific Northwest. Basement. Crawl space. The whole package. After a neighbor found radon levels above 4 pCi/L in his home, I got curious. I tested with a charcoal canister kit from the hardware store. It came back at 3.2 pCi/L. Below the EPA action level, but not zero.
That was the trigger. I wanted continuous monitoring, not a one-time snapshot. Radon fluctuates with weather, barometric pressure, and how much you open windows. A three-day test tells you almost nothing about long-term exposure.
Here is the fundamental problem air quality monitors solve: you cannot smell, see, or feel most indoor pollutants. CO2 is odorless. Radon is invisible. VOCs from a new sofa off-gas silently. You only notice when you get a headache, feel drowsy, or develop a cough weeks later. By then, the damage is done.
What the View Plus Actually Measures
The View Plus tracks six parameters: radon, CO2, VOCs (volatile organic compounds), PM2.5 (particulate matter), temperature, humidity, and air pressure. That is a broader sensor suite than most competitors at this price point.
The Airthings View Plus uses a passive radon sensor, meaning it takes readings over hours and days, not minutes. That is actually correct for radon, which does not change second-to-second. For CO2 and VOCs, it updates every 5 minutes. PM2.5 updates every 10 minutes.
The Sensor That Surprised Me Most
CO2. Hands down. I knew radon was my concern going in. But CO2 gave me the most actionable data. On nights with the bedroom door closed and windows shut, levels climbed past 1,500 ppm by morning. At 2,000 ppm, you get drowsy, headaches, and reduced cognitive function. Studies show decision-making performance drops 50% at 1,400 ppm compared to outdoor air at 400 ppm.
I started cracking the window an inch before bed. Next morning: 650 ppm. That single change was worth the price of the monitor.
What the Airthings View Plus Got Right
The View Plus nailed the basics. Setup took 4 minutes. Plug it in, connect to Wi-Fi, download the app. No calibration required. The sensors are factory-calibrated and the company says they last the lifetime of the device for radon. The CO2 sensor self-calibrates over time by assuming the lowest reading in 7 days is fresh outdoor air at 400 ppm.
Battery life on the backup battery is about 24 hours. That matters if you move it between rooms or have a power outage. The main unit plugs into USB-C, so you can use any phone charger.
The Dashboard That Actually Made Sense
The Airthings app gives you a color-coded dashboard. Green is good. Yellow is moderate. Red is bad. Each parameter gets its own card with a 7-day trend line. I could see exactly when CO2 spiked, when humidity dropped below 30%, and when radon crept above 2 pCi/L.
The web dashboard is better than the phone app. Bigger graphs, longer time ranges, and exportable CSV data. I downloaded a month of radon readings and plotted them in Excel. That level of access is rare for a consumer device.
The Alerts That Woke Me Up
You can set custom thresholds for each parameter. I set CO2 to alert at 1,200 ppm and radon at 3 pCi/L. The first time the radon alert fired, it was 3:00 AM on a rainy Tuesday. I got a push notification. The next day, I ran a longer-term test and found the average was 2.8 pCi/L. Not emergency-level, but worth monitoring.
Without those alerts, I would have never noticed the nighttime build-up.
The Three Things That Annoy Me About the View Plus
No product is perfect. Here is what frustrates me after six months.
PM2.5 Accuracy Is Suspect
The PM2.5 sensor uses a laser particle counter. On paper, it detects particles down to 0.3 microns. In practice, it seems to over-report. I ran the View Plus next to an IQAir AirVisual Pro ($299) for a week. The IQAir showed PM2.5 at 5-8 µg/m³ on a clear day. The View Plus showed 12-15 µg/m³. That is a 50-100% difference.
For a general trend monitor, it works. If you need lab-grade PM2.5 data for asthma or allergy management, look elsewhere. The uHoo Smart Air Monitor ($329) has a more accurate PM sensor, though it lacks radon detection.
Radon Readings Are Slow
The passive radon sensor takes 24 hours to stabilize after you first plug it in. Even then, short-term spikes can take 6-12 hours to register. That is physics, not a design flaw. But if you want real-time radon alerts, this is not that device. The Airthings Wave Plus ($199) uses the same sensor but has no display — you check readings via app or tap the top.
The Screen Is Small and Dim
The e-ink display shows one parameter at a time. You cycle through with a button on the side. The screen is readable in bright light but useless in a dark room. I mounted mine on a hallway wall and barely look at it. The app is where the real data lives.
How the Airthings View Plus Compares to Other Monitors
I tested three other monitors alongside the View Plus. Here is the real comparison.
| Monitor | Price | Radon | CO2 | PM2.5 | VOC | Display | Data Export |
|---|---|---|---|---|---|---|---|
| Airthings View Plus | $249 | Yes | Yes | Yes | Yes | e-ink, 1 line | CSV via web |
| Airthings Wave Plus | $199 | Yes | Yes | No | Yes | None | CSV via web |
| Awair Element | $149 | No | Yes | Yes | Yes | Color LCD | No |
| uHoo Smart Air Monitor | $329 | No | Yes | Yes | Yes | Color LCD | API access |
| IQAir AirVisual Pro | $299 | No | Yes | Yes | No | Color LCD | No |
The View Plus is the only monitor under $300 that includes radon. If radon is your primary concern, the choice is simple. If you do not care about radon, the Awair Element at $149 gives you CO2, PM2.5, VOCs, temperature, and humidity with a better screen and faster updates.
When You Should NOT Buy the Airthings View Plus
I have recommended this monitor to exactly three people. I told four others to buy something else.
Do not buy the View Plus if:
- You only care about PM2.5. The sensor is not accurate enough. Get the uHoo or IQAir.
- You want real-time data on a screen. The e-ink display is slow and dim. The Awair Element shows everything at a glance.
- You live in a rental and cannot mount it. The View Plus sits on a shelf or counter, but the sensor placement matters. It needs to be 3-5 feet off the ground, away from windows and doors. If you cannot place it properly, the data is useless.
- You need a portable monitor. The View Plus is AC-powered. The battery backup is for short outages, not daily carry. The Airthings Wave Mini ($99) runs on batteries and measures humidity, VOCs, and temperature, but not radon or CO2.
The One Mistake Almost Everyone Makes With Air Quality Monitors
People place the monitor in the living room or kitchen. That is wrong. The most important room for air quality monitoring is the bedroom. You spend 7-9 hours there every night. CO2 builds up. Radon accumulates. VOCs from bedding and furniture off-gas continuously.
I moved my View Plus from the living room to the bedroom after the first week. The living room readings were always green. The bedroom showed yellow every night. That is where the action is.
Second mistake: ignoring the humidity reading. The View Plus tracks humidity, and it matters more than most people think. Below 30%, viruses survive longer on surfaces. Above 60%, mold and dust mites thrive. I kept my bedroom between 40-50% after seeing the data. My sinuses thanked me.
Six Months of Data: The Verdict
After half a year, here is what I know. My average radon level is 2.1 pCi/L. Highest spike: 4.7 pCi/L during a week of heavy rain. My CO2 peaks at 1,800 ppm on closed-window nights. My humidity drops to 28% on cold winter days. My VOCs spike when I cook with the oven on self-clean mode.
The Airthings View Plus gave me data I acted on. I crack windows. I run a dehumidifier in winter. I stopped using the self-clean oven feature. I bought a CO2 monitor for my office because the View Plus showed me how bad enclosed spaces get.
For anyone concerned about radon, the Airthings View Plus is the best option under $300. No other consumer monitor combines radon detection with CO2, VOCs, and PM2.5 at this price. The PM2.5 sensor is mediocre, the screen is basic, and the radon readings are slow. But the core function — continuous, long-term air quality monitoring with actionable alerts — works. If radon is not your concern, save $100 and buy the Awair Element. If radon is, this is the one.