AirVisual does its best to provide accurate, reliable, real-time data. Our sources range from governmental stations to our own AirVisual Pro, and cover more than 10,000 cities worldwide. If you happen to notice some discrepancies between AirVisual information and other air pollution information providers, there might be a valid reason.

1. Update frequency: it is possible that the various apps and websites, particularly those relaying source data, to update at different times. This can cause different locations to show different data - some current, some outdated.

2. Air pollution index: be careful to ensure that the apps or websites you are comparing are using the same air quality index. Many countries have their own air pollution index, and some apps have also crafted their own system for representing the level of risk in the air - as a result it’s important to ensure you are comparing “apples to apples” with regards to pollution numbers. AirVisual allows users to choose from either the US and China standard international air pollution index (AQI) - these can be switched between in the settings of the app or Pro.

3. Data source: Different sources may be representing different source data. AirVisual displays both official government and Node data together on one platform. Not all apps, however, will display the same data set and some may produce citywide averages.

To read more about our air quality index, see the link below: