SmogRank / World / Europe / Germany / North Rhine-Westphalia
Most polluted cities in North Rhine-Westphalia, Germany
1 measured city, last 30 days; 0 above the WHO 24-hour guideline. The only one: Olpe at 3.4 µg/m³, #2,752 in the world.
About 0 people in this city breathed unhealthy air on an average day over the last 30 days.
Ranked by people: each city's population times its share of unhealthy days, those with a daily mean over 35.4 µg/m³ (US AQI 101+). That is how many people living there breathed unhealthy air on an average day. Only cities measured at 2 or more places at least 3 km apart are ranked: one monitor shouldn't speak for a whole city. Population is the city itself, not its wider metro area.
Cities coloured by their PM2.5 over the last 24 hours. Fires, smoke and ash: Oct 5, the newest UTC day mapped.
- 1Olpelow-cost sensors 0
Low-cost sensors: consumer units, counted only in cities with no government-grade monitor; they read close to reference monitors on the whole, but 15 to 25% high in humid air. How we use them.
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
Estimated: cities without a monitor
North Rhine-Westphalia 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 |
|---|---|
| Bochum | ≈ 11 µg/m³ |
| Hamm | ≈ 9 µg/m³ |
| Mülheim | ≈ 11 µg/m³ |
| Herne | ≈ 11 µg/m³ |
| Solingen | ≈ 10 µg/m³ |
| Neuss | ≈ 12 µg/m³ |
| Paderborn | ≈ 7 µg/m³ |
| Recklinghausen | ≈ 11 µg/m³ |
| Remscheid | ≈ 10 µg/m³ |
| Siegen | ≈ 7 µg/m³ |
| Bergisch Gladbach | ≈ 9 µg/m³ |
| Moers | ≈ 11 µg/m³ |
| Gütersloh | ≈ 10 µg/m³ |
| Düren | ≈ 8 µg/m³ |
| Iserlohn | ≈ 8 µg/m³ |
| Witten | ≈ 11 µg/m³ |
| Marl | ≈ 11 µg/m³ |
| Velbert | ≈ 11 µg/m³ |
| Minden | ≈ 10 µg/m³ |
| Dorsten | ≈ 12 µg/m³ |
| Castrop-Rauxel | ≈ 11 µg/m³ |
| Rheine | ≈ 9 µg/m³ |
| Viersen | ≈ 11 µg/m³ |
| Gladbeck | ≈ 12 µg/m³ |
| Arnsberg | ≈ 6 µg/m³ |
| Troisdorf | ≈ 9 µg/m³ |
| Wattenscheid | ≈ 11 µg/m³ |
| Bocholt | ≈ 10 µg/m³ |
| Detmold | ≈ 10 µg/m³ |
| Lippstadt | ≈ 8 µg/m³ |
| Dinslaken | ≈ 11 µg/m³ |
| Herten | ≈ 11 µg/m³ |
| Herford | ≈ 10 µg/m³ |
| Grevenbroich | ≈ 11 µg/m³ |
| Kerpen | ≈ 10 µg/m³ |
| Dormagen | ≈ 12 µg/m³ |
| Bergheim | ≈ 10 µg/m³ |
| Langenfeld | ≈ 12 µg/m³ |
| Stolberg | ≈ 9 µg/m³ |
| Hilden | ≈ 12 µg/m³ |
Bad-air episodes in North Rhine-Westphalia
- Belgium, France and 2 more countries, June 202625 June 2026, 1 day15 cities39 µg/m³peak, Unna
- Europe, 18 to 25 March 20268 days430 cities136 µg/m³peak, Łask
- Europe, 1 to 12 March 202612 days532 cities109 µg/m³peak, Radomsko
- Europe, January and February 202612 January to 12 February 2026, 32 days625 cities252 µg/m³peak, Travnik
- Germany and France, January 20266 January 2026, 1 day15 cities34 µg/m³peak, Speyer
- Europe, December 2025 to January 202625 December 2025 to 2 January 2026, 9 days189 cities110 µg/m³peak, Kempten (Allgäu)
Times when many cities around here had PM2.5 at twice their usual or more on the same days.
Use this board
SmogRank, most polluted cities in North Rhine-Westphalia, Germany, PM2.5, last 30 days to 6 Oct 2026, 23:00 UTC, smogrank.com/de/region/north-rhine-westphalia?w=30d.
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.
Updated 2026-10-06 23:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.