SmogRank / United States / California / Oakland

Oakland, month by month

Oakland has a measured daily mean on 1,342 days since 1 January 2023. Its worst month was January 2026, at 58 US AQI (13.1 µg/m³), 867th of 2,617 cities on that month's world ranking. Its cleanest was July 2025, at 26 US AQI (4.6 µg/m³). 2025 averaged 43 US AQI (7.8 µg/m³), against 40 US AQI (7.2 µg/m³) in 2024.

Every month since 2023

Each square is a month's mean PM2.5 in US AQI from Oakland's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Oakland marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Oakland's worst months

MonthUS AQIDays measuredWorld rankEpisode
January 2026 5813.1 µg/m³31 of 31867thof 2,617California and Oregon, United States, January 2026
December 2024 5712.2 µg/m³31 of 31654thof 2,616California and Oregon, United States, December 2024
December 2025 5611.8 µg/m³31 of 31996thof 3,006–
September 2023 5511.1 µg/m³30 of 30414thof 2,176California and Oregon, United States, September 2023
December 2023 5310.4 µg/m³30 of 31626thof 2,247–
November 2025 5310.2 µg/m³24 of 30996thof 2,715–

Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.

Oakland's worst days

DayUS AQIEpisode
20 Sept 2023 12746.1 µg/m³California and Oregon, United States, September 2023
7 Dec 2024 10135.5 µg/m³California and Oregon, United States, December 2024
22 Sept 2023 9834.2 µg/m³California and Oregon, United States, September 2023
21 Sept 2023 9633.1 µg/m³California and Oregon, United States, September 2023
19 Sept 2023 9029.9 µg/m³California and Oregon, United States, September 2023
8 Dec 2024 8929.7 µg/m³California and Oregon, United States, December 2024
11 Dec 2024 8326.3 µg/m³California and Oregon, United States, December 2024
30 Aug 2023 8225.5 µg/m³North-western United States and Canada, August 2023
15 Jan 2026 8125.0 µg/m³California and Oregon, United States, January 2026
23 Sept 2023 7924.0 µg/m³California and Oregon, United States, September 2023

Daily means, the highest since 1 Jan 2023; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.

Use this history

SmogRank, PM2.5 monthly and daily means, Oakland, United States, 1 Jan 2023 – 11 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/oakland/history (accessed 12 Oct 2026).

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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.

Oakland now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-12 23:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).