Air quality information
Air quality information
Learn about AQI, our data sources, and how we validate and visualize air quality data
27 articles
AWritten by Chloe, Kelsey and AirVisual


How can I access historical data on the IQAir platform?
A guide to the freely available historical air quality data provided on the IQAir website and app
Written by Chloe. Updated over a week ago
Reported AQI levels seem lower than it appears, visually
Reported air quality levels are too low. Published data appears to be incorrect.
Written by Kelsey. Updated over a week ago
What is AQI?
Guide to understanding the Air Quality Index
Written by Chloe. Updated over a week ago
What is the difference between the US AQI and WHO air quality guidelines?

Written by Chloe. Updated over a week ago
What is the difference between China & US AQI; 美国空气质量指数和中国空气质量指数有什么区别?

Written by Chloe. Updated over a week ago
What is the difference between Singapore’s Pollutant Standards Index and the U.S. Air Quality Index?
A
Written by AirVisual. Updated over a week ago
How is the Malaysian Air Pollution Index calculated?
Learn what is the difference between Malaysia's "API" and other air quality indexes (AQIs)
Written by Chloe. Updated over a week ago
How is AQI calculated without all 6 key pollutants?

Written by Chloe. Updated over a week ago
How accurate is AirVisual’s air quality data?
A
Written by AirVisual. Updated over a week ago
How is air quality data validated before publishing on the AirVisual platform?

Written by Chloe. Updated over a week ago
How can I check the data source of a station?
Learn which different data sources AirVisual uses to report air quality for cities and stations, and how to identify them
Written by Chloe. Updated over a week ago
What does the asterisk (*) mean on some locations' AQI?

Written by Chloe. Updated over a week ago
My city's data is unavailable on the AirVisual map

Written by Chloe. Updated over a week ago
Where does AirVisual get its air quality data from?
Learn which data sources AirVisual reports from to provide global air quality informationA
Written by AirVisual. Updated over a week ago
What determines the major cities ranking?

Written by Chloe. Updated over a week ago
Air quality forecast

Written by Chloe. Updated over a week ago
What is AirVisual Earth and how does it work?

Written by Chloe. Updated over a week ago
What is an air quality widget and how can I use one to display air quality information on my webpage?

Written by Chloe. Updated over a week ago
How can I access air pollution data through AirVisual's air quality API?

Written by Chloe. Updated over a week ago
Access AirVisual's AQI, Air quality and pollution API

Written by Chloe. Updated over a week ago
AirVisual API timestamp - how does it work?

Written by Chloe. Updated over a week ago
AirVisual’s outdoor data seems to differ from other sources. Why is this?

Written by Chloe. Updated over a week ago
Why are AirVisual and AirNow showing different AQI numbers?

Written by Chloe. Updated over a week ago
Why do Vietnamese government stations sometimes disappear from AirVisual’s map?
A
Written by AirVisual. Updated over a week ago
How are Hanoi’s AQI and the city rankings calculated?
A
Written by AirVisual. Updated over a week ago
How accurate is AirVisual’s data in Vietnam?
A
Written by AirVisual. Updated over a week ago
In Vietnam, where does AirVisual get its data from?
A
Written by AirVisual. Updated over a week ago