Chennai vs Dehradun
Side-by-side air quality comparison between Chennai and Dehradun.
Live AQI from Open-Meteo CAMS (~45 km global model, updated hourly). Multi-year history from CPCB station data via aqinow.co pipeline (2016–2024, station-level daily records).
AQI Comparison
Pollutant-level comparison (PM2.5, PM10, O3, NO2, SO2, CO)▾
| Pollutant | Chennai | Dehradun |
|---|---|---|
| PM2.5(µg/m³) | 11.70 | 14.40 |
| PM10(µg/m³) | 13.10 | 14.60 |
| NO₂(µg/m³) | 14.20 | 25.40 |
| SO₂(µg/m³) | 10.10 | 4.10 |
| O₃(µg/m³) | 56.00 | 71.00 |
| CO(µg/m³) | 308.00 | 350.00 |
CPCB Multi-Year History (2016–2024)
Summary
Overview
In 2024, Chennai averaged an AQI of 68 while Dehradun averaged 106 — a 38-point (56%) gap, with Dehradun the more polluted and Chennai the cleaner of the two. On 502 days when both cities reported, Dehradun was cleaner on 281 of them; the average daily gap was 53 AQI points.
Seasonality & days
Chennai peaks in December, while Dehradun peaks in January. Chennai logged 0% Severe days and 57.5% Good-or-Satisfactory days; Dehradun was 0% Severe and 62.8% Good-or-Satisfactory. Longest clean-air streaks: Chennai 53 days, Dehradun 41 days.
Year-over-year progress
Chennai has improved by 25 AQI points (26.9%) from 2017 to 2024; Dehradun has worsened by 19 AQI points (21.8%) over the same window. The worst recorded day for Chennai reached AQI 391 at Kodungaiyur (TNPCB) on 2021-05-14; Dehradun hit AQI 327 at Doon University (UKPCB) on 2024-01-19.
Station-level disparity
Chennai spans 9 CPCB stations with a 27-point spread (min 63, max 90); Dehradun spans 1 stations with a 0-point spread (min 98, max 98).
Verdict
🏆 Chennai has better air quality with an AQI of 20 compared to Dehradun's 24.