Kolkata vs Patna
Side-by-side air quality comparison between Kolkata and Patna.
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 | Kolkata | Patna |
|---|---|---|
| PM2.5(µg/m³) | 64.70 | 97.80 |
| PM10(µg/m³) | 69.40 | 109.40 |
| NO₂(µg/m³) | 18.10 | 40.50 |
| SO₂(µg/m³) | 13.10 | 18.90 |
| O₃(µg/m³) | 86.00 | 52.00 |
| CO(µg/m³) | 428.00 | 667.00 |
CPCB Multi-Year History (2016–2024)
Summary
Overview
In 2024, Kolkata averaged an AQI of 101 while Patna averaged 172 — a 71-point (70%) gap, with Patna the more polluted and Kolkata the cleaner of the two. On 2005 days when both cities reported, Kolkata was cleaner on 1684 of them; the average daily gap was 77 AQI points.
Seasonality & days
Kolkata peaks in January, while Patna peaks in December. Kolkata logged 1% Severe days and 47.800000000000004% Good-or-Satisfactory days; Patna was 7.5% Severe and 19.400000000000002% Good-or-Satisfactory. Longest clean-air streaks: Kolkata 75 days, Patna 30 days.
Year-over-year progress
Kolkata has improved by 76 AQI points (42.9%) from 2017 to 2024; Patna has improved by 40 AQI points (18.9%) over the same window. The worst recorded day for Kolkata reached AQI 453 at Rabindra Bharati University (WBPCB) on 2019-01-23; Patna hit AQI 491 at IGSC Planetarium Complex (BSPCB) on 2016-01-01.
Station-level disparity
Kolkata spans 7 CPCB stations with a 56-point spread (min 95, max 151); Patna spans 6 stations with a 39-point spread (min 154, max 193).
Verdict
🏆 Kolkata has better air quality with an AQI of 117 compared to Patna's 227. That's a significant difference of 110 points.