Air quality in Ontario

Air quality index (AQI) and PM2.5 air pollution in Ontario

LAST UPDATE (local time)

LIVE AQI CITY RANKING

Real-time Ontario
Most polluted city ranking

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#cityUS AQI
1 Kitchener

102

2 Wellington County

80

3 Sarnia

72

4 Guelph

70

5 London

67

6 Simcoe

63

7 Hamilton

62

8 Markham

60

9 Ancaster

57

10 Chatham

57

(local time)

SEE WORLD AQI RANKING

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LIVE AQI CITY RANKING

Real-time Ontario
Cleanest city ranking

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#cityUS AQI
1 North Bay

8

2 Oshawa

8

3 Parry Sound

12

4 Petawawa

12

5 Oakville

16

6 Cornwall

17

7 Barrie

21

8 Kirkland Lake

21

9 Newmarket

21

10 Almonte

22

(local time)

SEE WORLD AQI RANKING
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