What is the air quality in Toronto?

Toronto, Canada has an annual US AQI of 45 (Reasonable) and average PM2.5 of 8.5 µg/m³, ranking #461 of 5856 cities. Main pollutant: PM2.5.

What is the cleanest month in Toronto?

October is typically the cleanest month (AQI 38) and July the most polluted (AQI 53).

Where does Toronto's air quality data come from?

PM2.5: 1998–2026 (monitors 2001–2026, satellite 1998–2000; 2025–2026 provisional). Measured by government monitoring stations. Full sources are on the methodology page.

Toronto, Canada — Air Quality & Clean City Guide 2026

Toronto Air Quality Data

Global rank	City	Continent	AQI	PM2.5
461	Toronto, Canada	North America	AQI 45	PM2.5 8.5 µg/m³