WorldArrow icon
Arrow iconOntario

Air quality in Ontario

Air quality index (AQI⁺) and PM2.5 air pollution in Ontario • 05:49, Oct 30

Government of Ontario, Ministry of the EnvironmentOklahoma Department of Environmental Quality AnonymousJim GuilletNational Air Pollution Surveillance ProgramPiéEVCO**Chris Fournier@airqualitybrampton & airqualitybrampton@gmail.comHamilton Air Monitoring Network - HAMNMark OberemkGraydonSouth RichvaleMC2025Stacey SchacterstevepaulquinnBelltown - Oakley AveMeAmy CuriousKevin DamenNichols FamilyAnonymousElectric Vehicle Council of OttawaCSA HamiltonianMikoAirJayDeeVBbsummDGEC - GreensvilleAnonymous SlyyyMinistry of the Environment and the Fight against Climate ChangePaulAnonymousSteven RichierandalljhowardARTSean StewartJackBBriarwood Ave. Matt WojtowiczDataforge CanadaBradley SangerMichiruSWBijanWildflower Bee Farm Ontario and Nova ScotiaTimothy DresserBBT Batteries Ltd.Eric SteinCaptain Benjamin WillardLara TAnonymousHaig BlvdDave McKeeCanadian Air and Precipitation Monitoring NetworkKatwyks on the RiverPierreJpSMeS WepplerAnonymousMitch LPeter CornelisseGregMattAnonymous contributor
1 stations sponsored by The Foundation for Clean Air
Government of Ontario, Ministry of the EnvironmentOklahoma Department of Environmental Quality AnonymousJim GuilletNational Air Pollution Surveillance ProgramPiéEVCO**Chris Fournier@airqualitybrampton & airqualitybrampton@gmail.comHamilton Air Monitoring Network - HAMNMark OberemkGraydonSouth RichvaleMC2025Stacey SchacterstevepaulquinnBelltown - Oakley AveMeAmy CuriousKevin DamenNichols FamilyAnonymousElectric Vehicle Council of OttawaCSA HamiltonianMikoAirJayDeeVBbsummDGEC - GreensvilleAnonymous SlyyyMinistry of the Environment and the Fight against Climate ChangePaulAnonymousSteven RichierandalljhowardARTSean StewartJackBBriarwood Ave. Matt WojtowiczDataforge CanadaBradley SangerMichiruSWBijanWildflower Bee Farm Ontario and Nova ScotiaTimothy DresserBBT Batteries Ltd.Eric SteinCaptain Benjamin WillardLara TAnonymousHaig BlvdDave McKeeCanadian Air and Precipitation Monitoring NetworkKatwyks on the RiverPierreJpSMeS WepplerAnonymousMitch LPeter CornelisseGregMattAnonymous contributor
1 stations sponsored by The Foundation for Clean Air

Live most polluted city ranking

Real-time Ontario most polluted city ranking

#CitiesAQI⁺ US
1
The national flag of Canada

Cornwall

39

2
The national flag of Canada

Hawkesbury

32

3
The national flag of Canada

Amherstburg

31

4
The national flag of Canada

Brantford

29

5
The national flag of Canada

Wellington County

29

6
The national flag of Canada

Hawkesville

28

7
The national flag of Canada

Chatham

26

8
The national flag of Canada

Etobicoke

26

9
The national flag of Canada

Niagara on the Lake

26

10
The national flag of Canada

Oakville

25

Live cleanest city ranking

Real-time Ontario cleanest city ranking

#CitiesAQI⁺ US
1
The national flag of Canada

Ajax

0

2
The national flag of Canada

Algoma

0

3
The national flag of Canada

Greenstone

0

4
The national flag of Canada

Kasabonika

0

5
The national flag of Canada

Lindsay

0

6
The national flag of Canada

North York

0

7
The national flag of Canada

Sioux Narrows

0

8
The national flag of Canada

Bells Corners

1

9
The national flag of Canada

Breslau

1

10
The national flag of Canada

East York

1

Wildfires in Ontario

Real-time information

Active fires

--

Aerial view of multiple houses covered in haze.
external link icon

China Air Quality Alert

Small group of people cycling in morning smog.
external link icon

India Air Quality Alert

Polluted skies of Almaty.
external link icon

October 28, 2026: Almaty among top 10 most polluted cities in the world

Which is the most polluted city in Ontario?