SmogRank / World / Germany / North Rhine-Westphalia / January 2026

Most polluted cities in North Rhine-Westphalia, Germany, January 2026

34 cities in North Rhine-Westphalia, Germany ranked by their average PM2.5 over the 31 days. Worst: Unna at 19.4 µg/m³, #475 of 2,593 cities in the world. Cleanest: Roetgen at 6.7. A city needs measurements on 70% of the days to be ranked.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

← Wesel 13% 10%0
Every city in North Rhine-Westphalia, Germany ranked for January 2026, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Wesel
    13%
  2. 2Oberhausen
    11%
  3. 3Unna
    11%
  4. 4Bottrop
    11%
  5. 5Dortmund
    11%
  6. 6Bielefeld
    11%
  7. 7Gelsenkirchen
    11%
  8. 8Duisburg
    11%
  9. 9Essen
    11%
  10. 10Schwerte
    11%
  11. 11Olpelow-cost sensors
    10%
  12. 12Jüchen
    8%
  13. 13Borken
    8%
  14. 14Soest
    8%
  15. 15Ratingen
    7%
  16. 16Datteln
    7%
  17. 17Münster
    7%
  18. 18Krefeld
    7%
  19. 19Düsseldorf
    7%
  20. 20Hagen
    7%
  21. 21Titz
    7%
  22. 21Köln
    7%
  23. 23Kaldenkirchen
    7%
  24. 24Bonn
    7%
  25. 25Mönchengladbach
    7%
  26. 26Leverkusen
    7%
  27. 27Niederzier
    7%
  28. 28Sinnersdorf
    7%
  29. 29Hattingen
    7%
  30. 30Wuppertal
    7%
  31. 31Warstein
    4%
  32. 32Aachen
    4%
  33. 33Lüdenscheid
    0%
  34. 34Roetgen
    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.

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

All cities in the world, January 2026 · All cities in Germany, January 2026 · North Rhine-Westphalia now

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SmogRank, most polluted cities in North Rhine-Westphalia, Germany, PM2.5, January 2026, smogrank.com/de/region/north-rhine-westphalia/history/2026-01 (accessed 6 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.