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For current U.S. air conditions, start with AirNow. To find nearby official monitoring sites and explore past readings, use the EPA’s Interactive Map of Air Quality Monitors and AirData. For detailed historical records, download EPA files or query the Air Quality System (AQS). The best source depends on whether you need a current public AQI, a monitor’s location, a historical summary, or data you can analyze yourself.
Choose a source based on what you need
| Need | Start here | What it provides |
|---|---|---|
| Current conditions and forecasts | AirNow | Public AQI information and forecasts. Map readings are preliminary and can change. |
| Monitor locations and site details | EPA Interactive Map of Air Quality Monitors | Monitor locations and monitor-specific information, with daily and annual summary queries and downloads. |
| Historical summaries and visualizations | EPA AirData | Reports and visualizations, including daily and annual AQI or concentration summaries by city, county, or site. |
| Downloadable or row-level historical data | EPA AQS | Pre-generated data files for common uses or API access for more targeted queries. The API requires a key. |
| More local PM2.5 context, especially during smoke | AirNow Fire and Smoke Map | Official monitor information alongside community sensor readings, which need additional context and are not all equivalent to official instruments. |
Find official monitors near your neighborhood
- Open the EPA Interactive Map of Air Quality Monitors and search or navigate to your location.
- Inspect the sites shown nearby. Open a site’s details to see monitor-specific information, including the pollutant or network represented.
- Check the pollutant layer relevant to your question. The map includes monitors for carbon monoxide (CO), lead, nitrogen dioxide (NO2), ozone, particulate matter (PM10 and PM2.5), and sulfur dioxide (SO2), as well as specialized networks.
- Use the map’s daily or annual summary options when you want to explore past measurements, and download data if you need to work with it elsewhere.
A nearby dot is not proof that the site measures every pollutant you care about, nor that it represents every street in the neighborhood. A monitor records conditions at its own location; distance, local surroundings, and the pollutant all matter when judging how representative it is.
Check current conditions with AirNow
For a current public AQI view or forecast, search your location on AirNow. Use its map to inspect nearby readings and their timestamps. AirNow explains that its reported measurements come from state, local, or tribal agencies using EPA-approved reference or equivalent methods. AirNow is designed to communicate AQI to the public, while EPA’s AQS supports regulatory purposes.
AirNow states: “All readings are preliminary, unvalidated, and subject to change.” Its “no data” status means that nothing was reported for the most recent hour; it does not mean the air was clean or that pollution was absent. Check the time shown with a reading rather than treating a map value as timeless.
#1 Best Overall
- Know your air – An Alexa air quality monitor that makes it easy to understand what’s in your indoor air.
- Track and measure – Our indoor air quality monitor keeps tabs on 5 key factors: particulate matter (PM 2.5), volatile organic compounds (VOCs), carbon monoxide (CO), humidity, and temperature.
- Stay informed – Get an indication of current indoor air quality from the color-coded LED, and detailed information and an easy-to-understand air quality score in the Alexa app.
- Real-time alerts - Get notifications on your phone or announcements on Echo devices when Alexa detects poor indoor air quality.
- Automate climate control - Enable Routines to turn on or off your compatible Alexa devices, such as air purifiers, dehumidifiers, and fans, when the indoor air quality sensors detect changes.
Look up past readings in AirData or AQS
Use AirData for reports and common summaries
EPA AirData provides reports, visualizations, and downloadable daily and annual files. It is a practical route for looking at historical AQI or pollutant concentration summaries for a city, county, or monitoring site without building a custom data query.
Use AQS when you need detailed records
The Air Quality System (AQS) is EPA’s repository for air-quality data submitted by reporting agencies. Use the AQS API when you need more control over the records returned and can work with an API key; for common data needs, EPA’s pre-generated files can be simpler. Consult the relevant API or file documentation for available fields and query options.
Rank #2
- 【16-in-1 Air Quality Monitor Indoor】Experience the ultimate indoor air quality monitoring with our 16-in-1 Air Quality Monitor, offering real-time detection of 9 key parameters including CO2, PM2.5, PM1.0, PM10, HCHO, TVOC, Temperature, Humidity, AQI, and Time. With 7 distinct AQI alert buzzers, this air quality tester ensures your family breathes with ease.(*Note: "16-in-1" refers to the combination of 9 key detectable parameters and 7 types of AQI alert buzzers.)
- 【Crystal Clear 7-inch Large Display】Enjoy a 7-inch LED display for sharp, clear air quality readings. Provides an instant, comprehensive view of your indoor air without navigating through menus, with three brightness settings for any lighting condition
- 【External High-Precision Sensors with 0.001 Accuracy】Equipped with advanced external high-precision sensors, this device delivers unmatched accuracy (0.001 units) by directly sampling the air. Its innovative multi-sensor array and enhanced airflow design detect even the slightest environmental changes, allowing for instant response and optimal safety. (*Note: Avoid touching the sensors or exposing them to perfumes/strong odors to maintain accuracy.)
- 【Real-Time AQI Alert Buzzers】Our air quality monitor provides real-time monitoring and alerts for pollutants like CO2, PM2.5, PM1.0, PM10, HCHO, TVOC, Temperature, Humidity, and AQI, with 7 distinct alert functions. Stay informed with clear alerts and rest easy with a mute button to silence alarms. Your health and comfort are our priority. Toggle between Fahrenheit and Celsius instantly with a double-press of the "Power" button on this air quality detector.
- 【Up to 8 Hours of Runtime & Flexible USB-C Charging】 Enjoy up to 8 hours of continuous air quality monitoring on a full charge. The USB-C charging interface offers flexible power options and is compatible with widely available USB-C cables, while the included AC adapter provides convenient charging at home. Designed for effortless monitoring wherever you need it—from bedrooms and living spaces to your car and beyond.
Account for reporting and validation delays
Regulatory data in AQS may not be current. EPA says reporting agencies have 90 days after the end of a calendar quarter to submit data, and notes that the latest AQS data may be up to six months old. AirData supplements some recent AQI or daily-concentration displays with AirNow data, so a recent value shown there may not have the same status as an AQS record.
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If recent AQS data are missing, do not infer that no pollution occurred. Check AirNow for recent public information, consider the AQS submission and review lag, and contact the reporting agency if you need clarification about a site or its reporting schedule.
Rank #3
- High Accuracy & Fast Refresh Data: With this smart sensor, the PM2.5 accuracy is ±15 µg/m³ while temperature and humidity accuracies are ±0.54°F and ±3%RH.The two-second correction data feature shows the latest changes in PM2.5, temperature, and humidity.Keep sensor clear for accurate detection.
- Multifunctional Air Quality Detector: The GoveeLife Air Quality Monitor conveniently measures 3 important indexes for indoor air quality, including PM2.5, temperature, and humidity.
- Switchable Display: Press the top button for the clock & PM2.5 display. Long press for 2 seconds to switch to bright screen mode & night mode. The LED indicator displays 4 levels of ambient air quality. 2.4G Wi-Fi is required to display the time.
- Connect with GoveeHome Appliances: Set your target air quality and link with your other GoveeHome smart appliances. GoveeLife air purifiers, humidifiers, and space heaters will turn on and off automatically when the indoor air quality changes.
- H5106 needs to be connected to a power source and supports GoveeLife devices: Smart Air Purifiers - H7126, H7120, H7124, H712C, H7122, H7123; Humidifiers - H7140; Fans - H7100, H7102
Use community sensors as additional context
During smoke events or when official monitors are widely spaced, community sensor readings can add neighborhood-scale PM2.5 context. The AirNow Fire and Smoke Map includes PurpleAir sensor data with EPA-described quality controls and a correction equation. Sensor limitations still apply, and values from different maps may use different processing.
When comparing a sensor with an official monitor, record the source, pollutant, timestamp, and any stated correction or quality-screening details. Do not describe a low-cost sensor value as regulatory data or assume it is directly interchangeable with an official monitor reading.
Rank #4
- 【16-In-1 Comprehensive Air Quality Tracking】
- 【Easy Single-Tap Operation with Adjustable Audio Prompt】
Compare readings in context
Before using a reading to describe your neighborhood, check these four things:
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- Recency: What date and time does the value represent, and is it preliminary, validated, or otherwise qualified?
- Pollutant: Is it the pollutant relevant to your concern, such as PM2.5, ozone, or NO2?
- Location: How far is the monitor from the area of interest, and could local surroundings make its conditions unrepresentative?
- Method and status: Is the reading from an official monitor or a community sensor, and what measurement, correction, or quality information is available?
A number without its pollutant, timestamp, location, and source is not a meaningful neighborhood comparison.
When public monitors are not close enough
If you need an outdoor reading at a particular location that lacks a nearby public monitor, a sensor is an optional way to gather site-specific information. EPA siting guidance recommends choosing a location that represents the target area and avoiding obstructions that alter airflow. The sensor’s placement and surroundings affect what its readings can tell you; a single site should not automatically be treated as representative of an entire neighborhood.
These tools and pathways are U.S.-focused. AirNow’s interactive map also includes Canada and Mexico, but EPA’s data systems and the lag guidance described here should not be generalized to other countries’ monitoring agencies.
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