SmogRank / Countries / Costa Rica
Most polluted cities in Costa Rica
0 measured cities ranked by PM2.5, last 7 days.
No city has enough measurements for this window yet.
Good 0–9.0Moderate 9.1+Unhealthy for sensitive groups 35.5+Unhealthy 55.5+Very unhealthy 125.5+Hazardous 225.5+No data
Estimated: cities without a monitor
Costa Rica cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.
| City | 7-day estimate |
|---|---|
| San José estimated | ≈ 8 µg/m³ |
| Limón estimated | ≈ 5 µg/m³ |
| Alajuela estimated | ≈ 8 µg/m³ |
| Liberia estimated | ≈ 4 µg/m³ |
| Paraíso estimated | ≈ 8 µg/m³ |
| Puntarenas estimated | ≈ 6 µg/m³ |
| San Isidro estimated | ≈ 5 µg/m³ |
| Curridabat estimated | ≈ 8 µg/m³ |
| San Vicente estimated | ≈ 8 µg/m³ |
| San Vicente de Moravia estimated | ≈ 8 µg/m³ |
| San José estimated | ≈ 4 µg/m³ |
| Purral estimated | ≈ 8 µg/m³ |
| Turrialba estimated | ≈ 4 µg/m³ |
| San Miguel estimated | ≈ 8 µg/m³ |
| San Pedro estimated | ≈ 8 µg/m³ |
| San Rafael Abajo estimated | ≈ 8 µg/m³ |
| Quesada estimated | ≈ 4 µg/m³ |
| Cartago estimated | ≈ 8 µg/m³ |
| Chacarita estimated | ≈ 6 µg/m³ |
| San Juan estimated | ≈ 8 µg/m³ |
| Guadalupe estimated | ≈ 8 µg/m³ |
| Aserrí estimated | ≈ 8 µg/m³ |
| San Rafael estimated | ≈ 8 µg/m³ |
| San Felipe estimated | ≈ 8 µg/m³ |
| Patarrá estimated | ≈ 8 µg/m³ |
| Tejar estimated | ≈ 5 µg/m³ |
| Heredia estimated | ≈ 8 µg/m³ |
| San Pablo estimated | ≈ 8 µg/m³ |
| Cañas estimated | ≈ 5 µg/m³ |
| Guápiles estimated | ≈ 5 µg/m³ |
| Siquirres estimated | ≈ 4 µg/m³ |
| San Diego estimated | ≈ 8 µg/m³ |
| Esparza estimated | ≈ 6 µg/m³ |
| San Juan de Dios estimated | ≈ 8 µg/m³ |
| Nicoya estimated | ≈ 4 µg/m³ |
| San Rafael Arriba estimated | ≈ 8 µg/m³ |
Updated 2026-10-01 09:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.