SmogRank / Canada / Ontario

Air quality in Toronto

Ontario, Canada. PM2.5 from 4 reference monitors, updated hourly.

8.0 µg/m³
Good

Latest hour (03:00 UTC), 0.5× the WHO 24-hour guideline.

Rank

24 h
–
not enough data
7 days
#1,524
of 2,341 · 6.0 µg/m³
30 days
#1,542
of 2,337 · 5.5 µg/m³
Year
#1,160
of 2,166 · 8.6 µg/m³

Why it ranks here

Seasonal. Over the past year its worst months were July, averaging up to 19.5 µg/m³ against 5.2 in its cleanest month. Seasonal peaks usually come from heating, crop burning, fire or dust seasons.

Based on Toronto's own measurements; causes are the usual kinds for a pattern like this, not a confirmed source.

Last 4 days, hour by hour

15302026-09-30 23:00 UTC: 10.0 µg/m³2026-10-01 03:00 UTC: 8.0 µg/m³Sep 28Sep 29Sep 30

Times in UTC. Dashed line: WHO 24-hour guideline (15 µg/m³).

Every day for a year

SepNovDecJanFebMarAprMayJunJulAugSepMonWedFri2025-09-29: 8.1 µg/m³2025-09-30: 6.8 µg/m³2025-10-01: 4.2 µg/m³2025-10-02: 4.9 µg/m³2025-10-03: 9.9 µg/m³2025-10-04: 15.0 µg/m³2025-10-05: 16.9 µg/m³2025-10-06: 11.3 µg/m³2025-10-07: 4.6 µg/m³2025-10-08: 3.5 µg/m³2025-10-09: 3.0 µg/m³2025-10-10: 5.2 µg/m³2025-10-11: 7.2 µg/m³2025-10-12: 4.9 µg/m³2025-10-13: 5.3 µg/m³2025-10-14: 7.0 µg/m³2025-10-15: 2.4 µg/m³2025-10-16: 3.0 µg/m³2025-10-17: 5.6 µg/m³2025-10-18: 5.5 µg/m³2025-10-19: 7.4 µg/m³2025-10-20: 3.7 µg/m³2025-10-21: 6.3 µg/m³2025-10-22: 4.5 µg/m³2025-10-23: 4.6 µg/m³2025-10-24: 3.1 µg/m³2025-10-25: 3.5 µg/m³2025-10-26: 3.7 µg/m³2025-10-27: 3.9 µg/m³2025-10-28: 4.9 µg/m³2025-10-29: 5.1 µg/m³2025-10-30: 4.1 µg/m³2025-10-31: 2.4 µg/m³2025-11-01: 2.9 µg/m³2025-11-02: 6.8 µg/m³2025-11-03: 8.3 µg/m³2025-11-04: 4.2 µg/m³2025-11-05: 5.6 µg/m³2025-11-06: 3.3 µg/m³2025-11-07: 7.9 µg/m³2025-11-08: 2.4 µg/m³2025-11-09: 2.6 µg/m³2025-11-10: 2.3 µg/m³2025-11-11: 4.1 µg/m³2025-11-12: 7.1 µg/m³2025-11-13: 3.2 µg/m³2025-11-14: no data2025-11-15: no data2025-11-16: no data2025-11-17: no data2025-11-18: no data2025-11-19: no data2025-11-20: no data2025-11-21: 14.2 µg/m³2025-11-22: 5.3 µg/m³2025-11-23: 5.1 µg/m³2025-11-24: 5.8 µg/m³2025-11-25: 8.0 µg/m³2025-11-26: 7.7 µg/m³2025-11-27: 2.2 µg/m³2025-11-28: 2.1 µg/m³2025-11-29: 3.4 µg/m³2025-11-30: 4.9 µg/m³2025-12-01: 3.2 µg/m³2025-12-02: 7.4 µg/m³2025-12-03: 18.2 µg/m³2025-12-04: 5.5 µg/m³2025-12-05: 9.1 µg/m³2025-12-06: 14.8 µg/m³2025-12-07: 8.2 µg/m³2025-12-08: 6.9 µg/m³2025-12-09: 8.4 µg/m³2025-12-10: 9.8 µg/m³2025-12-11: 3.4 µg/m³2025-12-12: 5.4 µg/m³2025-12-13: 10.1 µg/m³2025-12-14: 4.0 µg/m³2025-12-15: 5.7 µg/m³2025-12-16: 16.4 µg/m³2025-12-17: 11.1 µg/m³2025-12-18: 11.6 µg/m³2025-12-19: 4.1 µg/m³2025-12-20: 4.8 µg/m³2025-12-21: 3.4 µg/m³2025-12-22: 9.5 µg/m³2025-12-23: 11.8 µg/m³2025-12-24: 5.6 µg/m³2025-12-25: 6.0 µg/m³2025-12-26: 2.6 µg/m³2025-12-27: 6.5 µg/m³2025-12-28: 7.5 µg/m³2025-12-29: 3.1 µg/m³2025-12-30: 2.8 µg/m³2025-12-31: 5.6 µg/m³2026-01-01: 2.8 µg/m³2026-01-02: 4.0 µg/m³2026-01-03: 6.0 µg/m³2026-01-04: 7.4 µg/m³2026-01-05: 10.7 µg/m³2026-01-06: 17.2 µg/m³2026-01-07: 14.7 µg/m³2026-01-08: 15.2 µg/m³2026-01-09: 5.5 µg/m³2026-01-10: 3.2 µg/m³2026-01-11: 4.0 µg/m³2026-01-12: 8.2 µg/m³2026-01-13: 10.2 µg/m³2026-01-14: 8.4 µg/m³2026-01-15: 3.0 µg/m³2026-01-16: 6.6 µg/m³2026-01-17: 9.3 µg/m³2026-01-18: 7.1 µg/m³2026-01-19: 6.5 µg/m³2026-01-20: 5.3 µg/m³2026-01-21: 9.9 µg/m³2026-01-22: 7.4 µg/m³2026-01-23: 3.7 µg/m³2026-01-24: 6.1 µg/m³2026-01-25: 3.5 µg/m³2026-01-26: 3.8 µg/m³2026-01-27: 12.2 µg/m³2026-01-28: 6.5 µg/m³2026-01-29: 5.6 µg/m³2026-01-30: 4.4 µg/m³2026-01-31: 3.8 µg/m³2026-02-01: 4.2 µg/m³2026-02-02: 17.7 µg/m³2026-02-03: 19.1 µg/m³2026-02-04: 7.0 µg/m³2026-02-05: 8.1 µg/m³2026-02-06: 19.7 µg/m³2026-02-07: 4.6 µg/m³2026-02-08: 6.2 µg/m³2026-02-09: 9.1 µg/m³2026-02-10: 17.0 µg/m³2026-02-11: 4.9 µg/m³2026-02-12: 4.0 µg/m³2026-02-13: 9.3 µg/m³2026-02-14: 18.0 µg/m³2026-02-15: 8.5 µg/m³2026-02-16: 18.8 µg/m³2026-02-17: 37.2 µg/m³2026-02-18: 8.0 µg/m³2026-02-19: 5.2 µg/m³2026-02-20: 7.7 µg/m³2026-02-21: 7.8 µg/m³2026-02-22: 8.4 µg/m³2026-02-23: 3.8 µg/m³2026-02-24: 4.6 µg/m³2026-02-25: 11.1 µg/m³2026-02-26: 5.8 µg/m³2026-02-27: 15.8 µg/m³2026-02-28: 5.0 µg/m³2026-03-01: 3.3 µg/m³2026-03-02: 5.7 µg/m³2026-03-03: 15.1 µg/m³2026-03-04: 30.6 µg/m³2026-03-05: 15.3 µg/m³2026-03-06: 9.6 µg/m³2026-03-07: 10.8 µg/m³2026-03-08: 3.7 µg/m³2026-03-09: 4.7 µg/m³2026-03-10: 10.2 µg/m³2026-03-11: 4.3 µg/m³2026-03-12: 2.6 µg/m³2026-03-13: 4.9 µg/m³2026-03-14: 3.0 µg/m³2026-03-15: 4.3 µg/m³2026-03-16: 4.1 µg/m³2026-03-17: 3.5 µg/m³2026-03-18: 7.6 µg/m³2026-03-19: 13.5 µg/m³2026-03-20: 12.9 µg/m³2026-03-21: 6.7 µg/m³2026-03-22: 9.7 µg/m³2026-03-23: 3.7 µg/m³2026-03-24: 5.7 µg/m³2026-03-25: 11.5 µg/m³2026-03-26: 20.2 µg/m³2026-03-27: 4.9 µg/m³2026-03-28: 5.0 µg/m³2026-03-29: 8.0 µg/m³2026-03-30: 12.3 µg/m³2026-03-31: 15.5 µg/m³2026-04-01: 3.5 µg/m³2026-04-02: 4.5 µg/m³2026-04-03: 8.4 µg/m³2026-04-04: 2.4 µg/m³2026-04-05: 3.0 µg/m³2026-04-06: 8.0 µg/m³2026-04-07: 4.5 µg/m³2026-04-08: 7.6 µg/m³2026-04-09: 10.0 µg/m³2026-04-10: 4.9 µg/m³2026-04-11: 5.8 µg/m³2026-04-12: 8.1 µg/m³2026-04-13: 9.3 µg/m³2026-04-14: 7.8 µg/m³2026-04-15: 8.2 µg/m³2026-04-16: 7.4 µg/m³2026-04-17: 3.3 µg/m³2026-04-18: 4.2 µg/m³2026-04-19: 3.3 µg/m³2026-04-20: 3.2 µg/m³2026-04-21: 5.4 µg/m³2026-04-22: 8.3 µg/m³2026-04-23: 7.1 µg/m³2026-04-24: 4.6 µg/m³2026-04-25: 4.5 µg/m³2026-04-26: 6.3 µg/m³2026-04-27: 5.3 µg/m³2026-04-28: 5.8 µg/m³2026-04-29: 3.2 µg/m³2026-04-30: 2.3 µg/m³2026-05-01: 4.0 µg/m³2026-05-02: 3.5 µg/m³2026-05-03: 8.3 µg/m³2026-05-04: 7.0 µg/m³2026-05-05: 6.1 µg/m³2026-05-06: 4.3 µg/m³2026-05-07: 5.1 µg/m³2026-05-08: 6.2 µg/m³2026-05-09: 9.7 µg/m³2026-05-10: 2.5 µg/m³2026-05-11: 1.5 µg/m³2026-05-12: 3.3 µg/m³2026-05-13: 5.3 µg/m³2026-05-14: 2.3 µg/m³2026-05-15: 4.7 µg/m³2026-05-16: 8.1 µg/m³2026-05-17: 17.7 µg/m³2026-05-18: 15.4 µg/m³2026-05-19: 6.8 µg/m³2026-05-20: 2.4 µg/m³2026-05-21: 3.1 µg/m³2026-05-22: 3.7 µg/m³2026-05-23: 3.0 µg/m³2026-05-24: 4.8 µg/m³2026-05-25: 9.9 µg/m³2026-05-26: 7.3 µg/m³2026-05-27: 4.9 µg/m³2026-05-28: 3.2 µg/m³2026-05-29: 4.7 µg/m³2026-05-30: 2.9 µg/m³2026-05-31: 3.4 µg/m³2026-06-01: 3.8 µg/m³2026-06-02: 5.7 µg/m³2026-06-03: 6.7 µg/m³2026-06-04: 10.9 µg/m³2026-06-05: 14.1 µg/m³2026-06-06: 8.9 µg/m³2026-06-07: 5.5 µg/m³2026-06-08: 5.9 µg/m³2026-06-09: 9.3 µg/m³2026-06-10: 8.3 µg/m³2026-06-11: 8.1 µg/m³2026-06-12: 5.0 µg/m³2026-06-13: 5.1 µg/m³2026-06-14: 4.3 µg/m³2026-06-15: 2.5 µg/m³2026-06-16: 4.3 µg/m³2026-06-17: 4.6 µg/m³2026-06-18: 3.3 µg/m³2026-06-19: 4.7 µg/m³2026-06-20: 2.9 µg/m³2026-06-21: 4.8 µg/m³2026-06-22: 4.9 µg/m³2026-06-23: 5.2 µg/m³2026-06-24: 5.7 µg/m³2026-06-25: 6.5 µg/m³2026-06-26: 10.7 µg/m³2026-06-27: 6.9 µg/m³2026-06-28: 8.2 µg/m³2026-06-29: 11.0 µg/m³2026-06-30: 15.4 µg/m³2026-07-01: 17.0 µg/m³2026-07-02: 16.2 µg/m³2026-07-03: 9.3 µg/m³2026-07-04: 7.2 µg/m³2026-07-05: 10.1 µg/m³2026-07-06: 8.9 µg/m³2026-07-07: 4.8 µg/m³2026-07-08: 5.9 µg/m³2026-07-09: 9.2 µg/m³2026-07-10: 7.9 µg/m³2026-07-11: 15.1 µg/m³2026-07-12: 22.3 µg/m³2026-07-13: 18.8 µg/m³2026-07-14: 12.6 µg/m³2026-07-15: 65.7 µg/m³2026-07-16: 136.0 µg/m³2026-07-17: 55.4 µg/m³2026-07-18: 56.3 µg/m³2026-07-19: 13.1 µg/m³2026-07-20: 13.7 µg/m³2026-07-21: 19.4 µg/m³2026-07-22: 2.8 µg/m³2026-07-23: 5.5 µg/m³2026-07-24: 6.8 µg/m³2026-07-25: 8.1 µg/m³2026-07-26: 11.3 µg/m³2026-07-27: 15.5 µg/m³2026-07-28: 12.4 µg/m³2026-07-29: 4.6 µg/m³2026-07-30: 4.9 µg/m³2026-07-31: 7.4 µg/m³2026-08-01: 11.6 µg/m³2026-08-02: 7.0 µg/m³2026-08-03: 3.9 µg/m³2026-08-04: 6.0 µg/m³2026-08-05: 7.6 µg/m³2026-08-06: 9.8 µg/m³2026-08-07: 12.1 µg/m³2026-08-08: 11.4 µg/m³2026-08-09: 6.1 µg/m³2026-08-10: 10.2 µg/m³2026-08-11: 7.8 µg/m³2026-08-12: 11.3 µg/m³2026-08-13: 9.1 µg/m³2026-08-14: 9.4 µg/m³2026-08-15: 4.9 µg/m³2026-08-16: 6.8 µg/m³2026-08-17: 5.5 µg/m³2026-08-18: 5.2 µg/m³2026-08-19: 6.7 µg/m³2026-08-20: 10.3 µg/m³2026-08-21: 7.9 µg/m³2026-08-22: 7.6 µg/m³2026-08-23: 4.6 µg/m³2026-08-24: 3.3 µg/m³2026-08-25: 6.4 µg/m³2026-08-26: 9.2 µg/m³2026-08-27: 7.7 µg/m³2026-08-28: 4.0 µg/m³2026-08-29: 7.1 µg/m³2026-08-30: 8.6 µg/m³2026-08-31: 6.8 µg/m³2026-09-01: 9.7 µg/m³2026-09-02: 7.0 µg/m³2026-09-03: 7.6 µg/m³2026-09-04: 5.5 µg/m³2026-09-05: 4.8 µg/m³2026-09-06: 5.1 µg/m³2026-09-07: 6.2 µg/m³2026-09-08: 6.6 µg/m³2026-09-09: 7.9 µg/m³2026-09-10: 4.1 µg/m³2026-09-11: 6.7 µg/m³2026-09-12: 6.8 µg/m³2026-09-13: 6.6 µg/m³2026-09-14: 3.2 µg/m³2026-09-15: 4.6 µg/m³2026-09-16: 5.5 µg/m³2026-09-17: 4.4 µg/m³2026-09-18: 3.9 µg/m³2026-09-19: 3.1 µg/m³2026-09-20: 3.2 µg/m³2026-09-21: 2.8 µg/m³2026-09-22: 3.0 µg/m³2026-09-23: 3.5 µg/m³2026-09-24: 4.0 µg/m³2026-09-25: 5.2 µg/m³2026-09-26: 4.3 µg/m³2026-09-27: 5.1 µg/m³2026-09-28: 5.8 µg/m³2026-09-29: 6.5 µg/m³2026-09-30: 11.2 µg/m³
Good 0–9.0Moderate 9.1+Unhealthy for sensitive groups 35.5+Unhealthy 55.5+Very unhealthy 125.5+Hazardous 225.5+No data

32 of 358 measured days were over the WHO 24-hour guideline.

Daily world rank

#1#2206OctNovDecJanFebMarAprMayJunJulAugSep

Rank on each day's board (1 = most polluted city that day).

2026 against 2025, month by month

15Jan 2025: 7.4 µg/m³Jan 2026: 7.2 µg/m³JanFeb 2025: 8.1 µg/m³Feb 2026: 10.6 µg/m³FebMar 2025: 6.4 µg/m³Mar 2026: 8.8 µg/m³MarApr 2025: 5.7 µg/m³Apr 2026: 5.7 µg/m³AprMay 2025: 4.9 µg/m³May 2026: 5.6 µg/m³MayJun 2025: 14.6 µg/m³Jun 2026: 6.8 µg/m³JunJul 2025: 15.6 µg/m³Jul 2026: 19.5 µg/m³JulAug 2025: 15.3 µg/m³Aug 2026: 7.6 µg/m³AugSep 2025: 7.5 µg/m³Sep 2026: 5.5 µg/m³SepOct 2025: 5.7 µg/m³OctNov 2025: 5.2 µg/m³NovDec 2025: 7.5 µg/m³Dec

Faded bars: 2025. A month shows once it has 10 measured days.

This week against past years

This weekThis week: 6.0 µg/m³6.020252025: 7.2 µg/m³7.2

Mean PM2.5 for 24 Sept to 30 Sept in each year. Dashed line: WHO 24-hour guideline.

Monitors

StationOperatorType
Toronto DowntownUS Public DomainAirNowReference
Toronto NorthUS Public DomainAirNowReference
Toronto WestUS Public DomainAirNowReference
Toronto EastUS Public DomainAirNowReference
AQ-Toronto-AnnexCC BY 4.0AirGradientLow-cost
aCC BY 4.0AirGradientLow-cost
NASA GSFC Rutgers Calib. N20CC0 1.0ClarityLow-cost
Downtown Toronto West EndCC BY 4.0AwassaLow-cost
North YorkCC BY 4.0PajamasLow-cost
33 Harbour SquareCC BY 4.0AirGradientLow-cost
Toronto West Harbourfront CC BY 4.0AirGradientLow-cost
Hillcrest VillageCC BY 4.0AirGradientLow-cost
Woodmount, North of MortimerCC BY 4.0AirGradientLow-cost
MPLCC BY 4.0AirGradientLow-cost
LeasideCC BY 4.0AirGradientLow-cost
Osler & DavenportCC BY 4.0AirGradientLow-cost
Keewatin (Toronto Midtown)CC BY 4.0AirGradientLow-cost
Toronto-Music GardenCC BY 4.0AirGradientLow-cost
Toronto - Fort YorkCC BY 4.0AirGradientLow-cost
The Air Near Balmy BeachCC BY 4.0AirGradientLow-cost
Maltida’s Fart TrackerCC BY 4.0AirGradientLow-cost
CortlandCC BY 4.0AirGradientLow-cost
CabbagetownCC BY 4.0AirGradientLow-cost

The city's value is the median of its reference monitors each hour; low-cost sensors are listed but not counted when reference monitors exist. Data via OpenAQ; licences as listed. How we rank. Embed this on your site.

Other cities in Canada

Kamloops 8.4Chilliwack 7.5Vernon 7.3Edmonton 7.2Red Deer 7.2Calgary 7.1Prince George 7.0Abbotsford 6.7Kelowna 6.6Sorel-Tracy 6.1Harewood 6.1Squamish 6.0

30-day averages, µg/m³. All of Canada →

Updated 2026-10-01 04:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.