How does the air quality in my city compare with other cities? What time of year has the best air quality? Has the air quality in my city improved? AirCompare provides local air quality information to help you make informed, health-protective decisions about moving or vacationing.

County Comparisons (Compare the air quality of counties within one or more states)

Summarize States (Choose up to 3 states)

Monthly Averages (Find the best time to visit)

Where is the best place in the United States to live to avoid air pollution? The best place to live may depend on whether you or your family have specific health concerns. People at greater risk from ground-level ozone are people with lung diseases, such as asthma, and children and adults who are active outdoors. At greatest risk from particle pollution are people with heart or lung disease, older adults (possibly because they may have undiagnosed heart or lung disease), and children. Learn more about how specific health concerns can affect the comparison. The links above provide health-specific air quality information in terms of the number of unhealthy days based on the Air Quality Index.

May 6, 2008 UPDATE: This site reflects the current Air Quality Index (AQI). The cut points for ozone were revised on March 12, 2008 along with the national ambient air quality standard for ozone. If you are a regular visitor to this site, you will notice the difference in the historical plots, specifically that there are more unhealthy days based on the revised ozone cut points. The current AQI does not yet account for the most recent PM2.5 standard which was revised on September 21, 2006.