Air Quality Lab — Seattle, United States
Air Quality Profile
Seattle reports an annual PM2.5 of 6.4 µg/m³. That's close to the WHO 2021 annual guideline (5 µg/m³) and well inside historically healthy ranges.
Seattle
United States
United StatesAnnual Average
GoodWHO annual classification
6.4µg/m³
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
PM2.5
5.75.7 µg/m³ — Good
6.66.6 µg/m³ — Good
6.16.1 µg/m³ — Good
5.45.4 µg/m³ — Good
4.84.8 µg/m³ — Excellent
5.25.2 µg/m³ — Good
6.76.7 µg/m³ — Good
6.76.7 µg/m³ — Good
8.98.9 µg/m³ — Good
7.07.0 µg/m³ — Good
7.07.0 µg/m³ — Good
6.36.3 µg/m³ — Good
Jan
Feb
Mar
Apr
May
Jun
5.75.7 µg/m³ — Good
6.66.6 µg/m³ — Good
6.16.1 µg/m³ — Good
5.45.4 µg/m³ — Good
4.84.8 µg/m³ — Excellent
5.25.2 µg/m³ — Good
Jul
Aug
Sep
Oct
Nov
Dec
6.76.7 µg/m³ — Good
6.76.7 µg/m³ — Good
8.98.9 µg/m³ — Good
7.07.0 µg/m³ — Good
7.07.0 µg/m³ — Good
6.36.3 µg/m³ — Good
Best months: Apr–JunWorst months: Sep–Nov
Excellent0–5 µg/m³Good5–10 µg/m³
Based on WUSTL PM2.5 dataset (2020–2024) · WHO 2021 thresholds
Confidence: ●●●
How air quality compares
Compared across United States
Seattle: 6.4 µg/m³. Typical range in United States: 6.4–7.8 µg/m³. Low anchor: Anchorage, 4.3 µg/m³. High anchor: Los Angeles, 13.8 µg/m³.
2,121 cities tracked