SmogRank / Calgary / Castlegar

Calgary vs Castlegar: PM2.5 compared

Over the last year, Castlegar's air was 10% more polluted than Calgary's: PM2.5 averaged 11.0 µg/m³ against 10.0, on the 322 days both cities were measured. Castlegar had the dirtier air on 148 of those days, Calgary on 169. Castlegar was over the WHO's daily guideline of 15 µg/m³ on 39 of them, Calgary on 54.

Right now

Calgary#848on the 24-hour board of 1,970, at 42 US AQI (7.5 µg/m³)
Castlegar#753on the 24-hour board of 1,970, at 46 US AQI (8.2 µg/m³)

The last year, day by day

Calgary
Castlegar
Each city's daily mean from 7 Oct 2025 to 6 Oct 2026, one stripe a day, coloured by band. A blank stripe is a day without a daily mean.

Month by month

Calgary, Nov 2025: 9.4 µg/m³Castlegar, Nov 2025: 9.0 µg/m³Nov2025Calgary, Dec 2025: 11.3 µg/m³Castlegar, Dec 2025: 6.3 µg/m³DecCalgary, Jan 2026: 12.6 µg/m³Castlegar, Jan 2026: 8.4 µg/m³Jan2026Calgary, Feb 2026: 9.5 µg/m³Castlegar, Feb 2026: 6.1 µg/m³FebCalgary, Mar 2026: 8.2 µg/m³Castlegar, Mar 2026: 6.2 µg/m³MarCalgary, Apr 2026: 6.4 µg/m³Castlegar, Apr 2026: 6.5 µg/m³AprCalgary, May 2026: 6.5 µg/m³Castlegar, May 2026: 5.9 µg/m³MayCalgary, Jun 2026: 4.3 µg/m³Castlegar, Jun 2026: 4.5 µg/m³JunCalgary, Jul 2026: 19.3 µg/m³Castlegar, Jul 2026: 19.7 µg/m³JulCalgary, Aug 2026: 17.3 µg/m³Castlegar, Aug 2026: 39.3 µg/m³AugCalgary, Sep 2026: 7.2 µg/m³Castlegar, Sep 2026: 8.0 µg/m³SepOct
Monthly means in µg/m³ over the days both cities were measured. Solid: Calgary. Faded: Castlegar. A month shows once both share 10 such days. Dashed line: the WHO daily guideline, 15 µg/m³.

Year by year

YearCalgaryCastlegarDays both measuredDays Calgary was worse
2026 so far5357246126
20255342344233
20245339359234
20235954282176

Means in US AQI over the days both cities were measured that year; a year shows once they share 30 such days.

Each city's worst days

Calgary

Castlegar

Daily means in US AQI, with µg/m³ beside them, since the index stops at its top value, over the days both cities were measured in the last year. Each date opens that day's world board.

Compare either city with another

Calgary

Side by side with Airdrie (the nearest), Gujranwala (the world's worst on 30 days).

Castlegar

Side by side with Creston (the nearest), Edmonton (Canada's 2nd worst on 30 days), Gujranwala (the world's worst on 30 days).

Use this page

SmogRank, PM2.5 daily means compared, Calgary and Castlegar, 7 Oct 2025 – 6 Oct 2026, smogrank.com/compare/ca-calgary/ca-castlegar (accessed 7 Oct 2026).

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

The same rules as every SmogRank figure: reference monitors first, and a day counts with 18 measured hours. How we measure.

Updated 2026-10-07 08:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.