Air quality
Air quality in Chāpra today
Updated
Unhealthy (US AQI 166) Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed. Model estimate for Mon, Oct 26, 6:30 am (01:00 UTC).
Live AQI, PM2.5, PM10 and ozone for Chāpra, Bihar, India, with a 48-hour forecast and the best time to be outside.
- US AQI now
- 166 Unhealthy
- PM2.5
- 135 µg/m³ 9× WHO 24-h guideline
- PM10
- 146 µg/m³
- Ozone
- 50 µg/m³
- Dominant pollutant
- PM2.5 sub-index 166
- Best hour today
- 6:30 am AQI 166
- European AQI
- 98
Air quality in Chāpra right now
Right now the modelled US Air Quality Index for Chāpra, Bihar, India is 166, which falls in the "Unhealthy" band (up to 200). Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed.
The index is driven mainly by PM2.5, whose own sub-index is 166. Fine and coarse particles come from traffic, heating, industry, dust and smoke; they build up on calm nights and clear when wind or rain arrives.
PM2.5 is 135 µg/m³, 9 times the WHO 24-hour guideline of 15 µg/m³; PM10 is 146 µg/m³ against a guideline of 45; ozone is 50 µg/m³ (below the WHO 8-hour level of 100); nitrogen dioxide is 39 µg/m³ (above the 24-hour guideline of 25).
Also this hour: carbon monoxide 675 µg/m³.
Chāpra AQI forecast: next 48 hours
Over the next 24 hours the AQI is forecast to range from 166 around Mon 6:30 am to 177 around Tue 5:30 am, staying "Unhealthy" throughout.
The following day looks similar, averaging about 175.
| Local time (Asia/Kolkata) | US AQI | Category | PM2.5 µg/m³ | PM10 µg/m³ | Ozone µg/m³ |
|---|---|---|---|---|---|
| Mon 6:30 am | 166 | Unhealthy | 135 | 146 | 50 |
| Mon 9:30 am | 168 | Unhealthy | 48.5 | 55 | 147 |
| Mon 12:30 pm | 169 | Unhealthy | 34.3 | 41 | 188 |
| Mon 3:30 pm | 168 | Unhealthy | 33.3 | 40 | 162 |
| Mon 6:30 pm | 169 | Unhealthy | 75 | 80 | 73 |
| Mon 9:30 pm | 170 | Unhealthy | 128.1 | 133 | 17 |
| Tue 12:30 am | 173 | Unhealthy | 146.7 | 152 | 9 |
| Tue 3:30 am | 176 | Unhealthy | 141.1 | 147 | 14 |
| Tue 6:30 am | 177 | Unhealthy | 148.5 | 153 | 45 |
| Tue 9:30 am | 178 | Unhealthy | 57.2 | 61 | 151 |
| Tue 12:30 pm | 179 | Unhealthy | 37.7 | 43 | 207 |
| Tue 3:30 pm | 179 | Unhealthy | 37.5 | 42 | 185 |
| Tue 6:30 pm | 179 | Unhealthy | 63.8 | 68 | 106 |
| Tue 9:30 pm | 177 | Unhealthy | 78.5 | 82 | 66 |
| Wed 12:30 am | 172 | Unhealthy | 80.8 | 84 | 56 |
| Wed 3:30 am | 166 | Unhealthy | 76.6 | 79 | 51 |
| Wed 6:30 am | 160 | Unhealthy | 91.7 | 95 | 54 |
Every third hour of the CAMS forecast via Open-Meteo. US AQI uses rolling averages (24 h for particles, 8 h for ozone), so it moves more slowly than the hourly concentrations.
Best time to be outside in Chāpra today
Between 6 am and 9 pm local time, the cleanest air today is forecast around 6:30 am (AQI 166, Unhealthy) and the worst around 8:30 pm (AQI 170). The difference across the day is small, so timing matters little.
Chāpra vs the rest of India
Across 260 India cities we track, the average US AQI right now is 116 (Unhealthy for Sensitive Groups). Chāpra at 166 is 50 points worse than average.
For context, the median across 3,909 cities worldwide is 57.
Air quality in cities near Chāpra
| City | Distance | US AQI | Category | PM2.5 µg/m³ |
|---|---|---|---|---|
| Patna | 44 km | 158 | Unhealthy | 105.9 |
| Muzaffarpur | 75 km | 162 | Unhealthy | 118.7 |
| Bihār Sharīf | 101 km | 152 | Unhealthy | 79.9 |
| Dhāka, Bihar | 108 km | 178 | Unhealthy | 156 |
| Gaya | 112 km | 139 | Unhealthy for Sensitive Groups | 66.4 |
| Aurangābād, Bihar | 120 km | 152 | Unhealthy | 59.8 |
| Darbhanga | 122 km | 155 | Unhealthy | 102.4 |
| Kushinagar | 137 km | 155 | Unhealthy | 87.5 |
Model vs measured
We found no measured PM2.5 sensor cell within 25 km of Chāpra, so the numbers on this page are model estimates. Models capture regional pollution well but can miss very local sources such as a busy road or a nearby fire.
Wildfire smoke
PM2.5 is forecast to reach 149 µg/m³ in the next 24 hours while NASA satellites detected 212 fire hotspots within 300 km in the last day (nearest about 55 km away). Smoke is a likely contributor: keep windows closed, run an air purifier or HVAC filter, and check the fire map before heading out.
Advice for sensitive groups
At 166, children, older adults, pregnant people and anyone with asthma, COPD or heart disease should limit time outdoors, especially strenuous activity. A well-fitted N95/FFP2 mask cuts particle exposure; it does not filter ozone.
What the US AQI numbers mean
| US AQI | Category | What it means |
|---|---|---|
| 0-50 | Good | Air quality is satisfactory and poses little or no risk; a good time for outdoor activity. |
| 51-100 | Moderate | Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors. |
| 101-150 | Unhealthy for Sensitive Groups | People with heart or lung disease, older adults, children and teens should cut back on prolonged or heavy exertion outdoors. |
| 151-200 | Unhealthy | Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed. |
| 201-300 | Very Unhealthy | Health alert: everyone should avoid prolonged or heavy exertion outdoors, and sensitive groups should stay indoors. |
| 301-500 | Hazardous | Emergency conditions: everyone should avoid all outdoor physical activity and stay indoors with filtered air if possible. The scale tops out at 500; heavier dust or smoke is shown as 500. |
Values on this page are modelled by CAMS (Copernicus) and served by Open-Meteo; they are estimates for the area around the city centre, not readings from an official monitor.
Nearby cities
More for Chāpra
Air quality elsewhere
Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS), NASA FIRMS.