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Air quality in Ontario
Air quality index (AQI) and PM2.5 air pollution in Ontario
LIVE AQI CITY RANKING
Real-time Ontario
Most polluted city ranking
| # | city | US AQI |
|---|---|---|
| 1 | Woodstock | 78 |
| 2 | London | 69 |
| 3 | Kitchener | 68 |
| 4 | Kingston | 62 |
| 5 | Cambridge | 58 |
| 6 | St. Catharines | 57 |
| 7 | Waterloo | 56 |
| 8 | Grand Bend | 53 |
| 9 | Niagara Falls | 53 |
| 10 | Fort Erie | 52 |
(local time)
SEE WORLD AQI RANKINGAIR QUALITY DATA CONTRIBUTORS
93 Contributors
See all
LIVE AQI CITY RANKING
Real-time Ontario
Cleanest city ranking
| # | city | US AQI |
|---|---|---|
| 1 | Sioux Narrows | 4 |
| 2 | Richmond Hill | 6 |
| 3 | Sudbury | 6 |
| 4 | Almonte | 7 |
| 5 | Orillia | 8 |
| 6 | Ottawa | 8 |
| 7 | Renfrew | 8 |
| 8 | North Bay | 12 |
| 9 | Sarnia | 13 |
| 10 | Timmins | 15 |
(local time)
SEE WORLD AQI RANKING
3D animated air pollution map
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The latest air quality news and resources.
Ontario air quality data attribution
93Contributors
- Hamilton Air Monitoring Network - HAMN
8 stations
- Township of SNNF
1 station
3 Government Contributors
- DGEC - Greensville
1 station
- Electric Vehicle Council of Ottawa
1 station
- EVCO
1 station
National Air Pollution Surveillance Program2 stations
4 Non-profit organization Contributors
- Kevin Damen
1 station
MikoAirOne1 station
- Anonymous
1 station
- Jim Guillet
1 station
- bsumm
1 station
Chris Fournier1 station
Slyyy1 station
JackB1 station
Christopher Trevors1 station
- Anonymous
1 station
Nichols Family1 station
- Bruce Buckley
1 station
Graydon1 station
- IQAir Lab
1 station
Anonymous1 station
CS3 stations
- VB
1 station
- randalljhoward
1 station
- **
1 station
- Bijan
1 station
- Libby
1 station
- Mark Douglas Wessel
1 station
- JayDee
1 station
Me1 station
- Keevabay
1 station
25 Individual Contributors
61 Anonymous contributors61 stations
61 Anonymous Contributors
Which is the most polluted city in Ontario?
- Woodstock 78
- London 69
- Kitchener 68
- Kingston 62
- Cambridge 58
- St. Catharines 57
- Amherstburg 56
- Waterloo 56
- Grand Bend 53
- Niagara Falls 53
- Fort Erie 52
- Port Colborne 52
- Walpole Island 52
- Welland 51
- Brantford 50
- Thorold 50
- Binbrook 47
- Norfolk County 46
- Simcoe 46
- Wellington County 46
- Aylmer 45
- Chatham 45
- St. Thomas 45
- Windsor 45
- Ancaster 44
- Dorchester 44
- Ingersoll 43
- Brant 42
- Delaware 42
- Etobicoke 41
- Guelph 41
- Niagara on the Lake 41
- East York 40
- Paris 40
- Petrolia 40
- Bluewater 39
- North York 38
- Willowdale 38
- Concord 37
- Gananoque 37
- Hamilton 37
- Port Stanley 37
- Pickering 34
- Stratford 34
- Angus 33
- Egbert 33
- Newmarket 33
- Oakville 33
- Pickle Lake 33
- Barrie 32
- Camlachie 32
- Keswick 32
- Orangeville 32
- Oshawa 32
- Picton 32
- Prince Edward 32
- Deseronto 31
- Experimental Lakes 31
- Greater Napanee 31
- Napanee Downtown 31
- Skatepark 31
- Wasaga Beach 31
- Lambton Shores 30
- Shelburne 30
- Belleville 29
- Cobourg 29
- Collingwood 29
- Cornwall 29
- Omemee 29
- Prescott 29
- South Huron 29
- Lindsay 28
- North Perth 28
- Hanover 27
- Hawkesbury 27
- Huron East 27
- Morrisburg 27
- Blyth 26
- Midland 26
- Thunder Bay 26
- Wingham 26
- Bonner Lake 25
- Goderich 25
- Kincardine 25
- Quinte West 25
- Sault Ste Marie 25
- Milton 24
- Burlington 23
- Ajax 22
- Brockville 22
- Parry Sound 22
- Toronto 22
- Algoma 21
- Brampton 21
- Casselman 21
- Coldwater 21
- Mississauga 21
- Smiths Falls 21
- Bourget 20
- Dorset 20
- Markham 20
- Peterborough 20
- Tiverton 20
- Perth 19
- Wendover 18
- Clarence-Rockland 17
- Gravenhurst 17
- Innisfil 17
- Owen Sound 17
- Scarborough 17
- Vaughan 17
- Bells Corners 16
- Carleton Place 16
- Nepean 16
- Tobermory 16
- Timmins 15
- Uxbridge 15
- Bracebridge 14
- Minden Hills 13
- Sarnia 13
- Bancroft 12
- North Bay 12
- Arnprior 11
- Ear Falls 10
- Red Lake 10
- Dryden 8
- Greenstone 8
- Hearst 8
- Orillia 8
- Ottawa 8
- Renfrew 8
- Almonte 7
- Deep River 7
- Hornepayne 7
- Huntsville 7
- Pembroke 7
- Petawawa 7
- Iroquois Falls 6
- Kapuskasing 6
- Richmond Hill 6
- Sudbury 6
- Kirkland Lake 5
- Marathon 5
- Mattawa 5
- Nestor Falls 5
- Powassan 5
- South River 5
- Atikokan 4
- Elliot Lake 4
- Englehart 4
- Espanola 4
- Fort Frances 4
- Little Current 4
- Neebing 4
- Rayside-Balfour 4
- Sioux Narrows 4
- Temiskaming Shores 4
- Thessalon 4
AQI US, Metric