Coimbatore vs Kolkata
Side-by-side air quality comparison between Coimbatore and Kolkata.
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 | Coimbatore | Kolkata |
|---|---|---|
| PM2.5(µg/m³) | 2.40 | 71.70 |
| PM10(µg/m³) | 2.70 | 75.70 |
| NO₂(µg/m³) | 4.70 | 22.30 |
| SO₂(µg/m³) | 2.10 | 12.00 |
| O₃(µg/m³) | 40.00 | 60.00 |
| CO(µg/m³) | 154.00 | 392.00 |
CPCB Multi-Year History (2016–2024)
Summary
Overview
In 2024, Coimbatore averaged an AQI of 66 while Kolkata averaged 101 — a 35-point (53%) gap, with Kolkata the more polluted and Coimbatore the cleaner of the two. On 1005 days when both cities reported, Coimbatore was cleaner on 859 of them; the average daily gap was 88 AQI points.
Seasonality & days
Coimbatore peaks in November, while Kolkata peaks in January. Coimbatore logged 0% Severe days and 90.5% Good-or-Satisfactory days; Kolkata was 1% Severe and 47.800000000000004% Good-or-Satisfactory. Longest clean-air streaks: Coimbatore 32 days, Kolkata 75 days.
Year-over-year progress
Coimbatore has improved by 5 AQI points (7%) from 2019 to 2024; Kolkata has improved by 76 AQI points (42.9%) over the same window. The worst recorded day for Coimbatore reached AQI 279 at SIDCO Kurichi (TNPCB) on 2024-09-28; Kolkata hit AQI 453 at Rabindra Bharati University (WBPCB) on 2019-01-23.
Station-level disparity
Coimbatore spans 2 CPCB stations with a 1-point spread (min 63, max 64); Kolkata spans 7 stations with a 56-point spread (min 95, max 151).
Verdict
🏆 Coimbatore has better air quality with an AQI of 4 compared to Kolkata's 140. That's a significant difference of 136 points.