Toronto Air Quality

Stay informed with real-time air quality updates for a healthier life.

Find Local Companies to Help Clean Your Air

Toronto, CA

5:20 am, May 19, 2025

10°C

overcast clouds

72 %

1014 mb

21 mph

Wind Gust: 28 mph

Clouds: 100%

Visibility: 10 km

Sunrise: 5:48 am

Sunset: 8:40 pm

Air Quality: Toronto

About Air Quality

Pollutant Information

Understanding Air Quality Index (AQI)

The Air Quality Index (AQI) is used for reporting daily air quality. It tells you how clean or polluted your air is, and what associated health effects might be a concern for you.

The AQI focuses on health effects you may experience within a few hours or days after breathing polluted air.

AQI Scale

0-50 (Good) Air quality is considered satisfactory, and air pollution poses little or no risk.

51-100 (Moderate) Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people.

101-150 (Unhealthy for Sensitive Groups) Members of sensitive groups may experience health effects. The general public is not likely to be affected.

151-200 (Unhealthy) Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects.

201-300 (Very Unhealthy) Health warnings of emergency conditions. The entire population is more likely to be affected.

301+ (Hazardous) Health alert: everyone may experience more serious health effects.

Common Air Pollutants

PM2.5 – Fine particulate matter less than 2.5 micrometers in diameter. These tiny particles can penetrate deep into the lungs and even enter the bloodstream.

PM10 – Inhalable particles, with diameters generally 10 micrometers and smaller. These can deposit in the airways.

O3 (Ozone) – A gas that occurs both in the Earth’s upper atmosphere and at ground level. Ground-level ozone can harm lung function and irritate the respiratory system.

NO2 (Nitrogen Dioxide) – A highly reactive gas formed when fuel is burned at high temperatures. It can cause inflammation of the airways and reduced lung function.

SO2 (Sulfur Dioxide) – A gas produced from burning fossil fuels containing sulfur. It can cause respiratory issues and make breathing difficult.

CO (Carbon Monoxide) – A colorless, odorless gas that can be harmful when inhaled in large amounts. It reduces oxygen delivery to the body’s organs.

Data provided by the World Air Quality Index Project

Bestseller #1

100PCs Black Disposable Face Mask 3-Ply Breathable & Comfortable …

$9.99

Buy on Amazon

Bestseller #2

3M Rugged Comfort Half Facepiece Reusable Respirator 6503, NIOSH,…

$26.48

Buy on Amazon

Bestseller #3

GVS Elipse P100 Dust Half Mask Respirator with replaceable and re…

$34.99

Buy on Amazon

Toronto Air Insights

Understanding Toronto’s Air Quality Changes: Key Factors from Traffic to Weather Patterns

Introduction to Air Quality in Toronto Air quality is a significant concern for urban centers such as Toronto, where a…

3/23/2025
Seasonal Air Quality Trends in Toronto: When and Why Air Quality Fluctuates

Introduction to Air Quality in Toronto Air quality refers to the condition of the air within our environment, primarily concerning…

3/23/2025