Air Quality
3.5/5
15.1 µg/m³Sensitive Groups
Air Quality Profile
San Francisco reports an annual PM2.5 of 15.1 µg/m³. That's meaningfully above the WHO 2021 guideline of 5 µg/m³ yet within the EU annual limit of 25 µg/m³.
San Francisco
El Salvador
El SalvadorAnnual Average
ModerateWHO annual classification
15.1µg/m³
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
PM2.5
8.58.5 µg/m³ — Good
1212 µg/m³ — Fair
1111 µg/m³ — Fair
2323 µg/m³ — Moderate
1919 µg/m³ — Moderate
1616 µg/m³ — Moderate
1414 µg/m³ — Fair
1616 µg/m³ — Moderate
1818 µg/m³ — Moderate
1919 µg/m³ — Moderate
1313 µg/m³ — Fair
1212 µg/m³ — Fair
Jan
Feb
Mar
Apr
May
Jun
8.58.5 µg/m³ — Good
1212 µg/m³ — Fair
1111 µg/m³ — Fair
2323 µg/m³ — Moderate
1919 µg/m³ — Moderate
1616 µg/m³ — Moderate
Jul
Aug
Sep
Oct
Nov
Dec
1414 µg/m³ — Fair
1616 µg/m³ — Moderate
1818 µg/m³ — Moderate
1919 µg/m³ — Moderate
1313 µg/m³ — Fair
1212 µg/m³ — Fair
Best months: Jan–MarWorst months: Apr–May, Oct
Good5–10 µg/m³Fair10–15 µg/m³Moderate15–25 µg/m³
Based on WUSTL PM2.5 dataset (2020–2024) · WHO 2021 thresholds
Confidence: ●●●
Air Quality Profile
San Francisco reports an annual PM2.5 of 15.1 µg/m³. That's meaningfully above the WHO 2021 guideline of 5 µg/m³ yet within the EU annual limit of 25 µg/m³.
San FranciscoEl Salvador
El SalvadorAnnual Average
ModerateWHO annual classification
15.1µg/m³
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
PM2.5
8.58.5 µg/m³ — Good
1212 µg/m³ — Fair
1111 µg/m³ — Fair
2323 µg/m³ — Moderate
1919 µg/m³ — Moderate
1616 µg/m³ — Moderate
1414 µg/m³ — Fair
1616 µg/m³ — Moderate
1818 µg/m³ — Moderate
1919 µg/m³ — Moderate
1313 µg/m³ — Fair
1212 µg/m³ — Fair
Jan
Feb
Mar
Apr
May
Jun
8.58.5 µg/m³ — Good
1212 µg/m³ — Fair
1111 µg/m³ — Fair
2323 µg/m³ — Moderate
1919 µg/m³ — Moderate
1616 µg/m³ — Moderate
Jul
Aug
Sep
Oct
Nov
Dec
1414 µg/m³ — Fair
1616 µg/m³ — Moderate
1818 µg/m³ — Moderate
1919 µg/m³ — Moderate
1313 µg/m³ — Fair
1212 µg/m³ — Fair
Best months: Jan–MarWorst months: Apr–May, Oct
Good5–10 µg/m³Fair10–15 µg/m³Moderate15–25 µg/m³
Based on WUSTL PM2.5 dataset (2020–2024) · WHO 2021 thresholds
Confidence: ●●●
Who thrives in San Francisco
Things to consider in San Francisco
PM2.5 annual average of 15.1 µg/m³ exceeds the WHO interim target of 15 µg/m³. The WHO guideline value is 5 µg/m³.
Data sources: WHO (air quality), OECD (safety).
Why not San Francisco?
Why not San Francisco? Honestly, air quality could be better — San Francisco's 15.1 µg/m³ annual PM2.5 is above WHO guidelines, though still within ranges common for larger cities.
Frequently asked about San Francisco
▶How many sunny days does San Francisco have per year?
San Francisco averages approximately 308 sunny days per year, based on historical climate data.
▶What is the air quality in San Francisco?
San Francisco has an annual PM2.5 concentration of 15.1 µg/m³, classified as "Moderate" by WHO standards. Above WHO targets. Some respiratory effects possible with prolonged exposure.