Air quality
Air quality in Zagreb today
Updated
Moderate (US AQI 62) Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors. Model estimate for Sun, Oct 25, 7:00 pm (18:00 UTC).
Live AQI, PM2.5, PM10 and ozone for Zagreb, Croatia, with a 48-hour forecast and the best time to be outside.
- US AQI now
- 62 Moderate
- PM2.5
- 18 µg/m³ 1.2× WHO 24-h guideline
- PM10
- 25 µg/m³
- Ozone
- 47 µg/m³
- Dominant pollutant
- PM2.5 sub-index 62
- Best hour tomorrow
- 4:00 pm AQI 55
- European AQI
- 42
Air quality in Zagreb right now
Right now the modelled US Air Quality Index for Zagreb, Croatia is 62, which falls in the "Moderate" band (up to 100). Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors.
The index is driven mainly by PM2.5, whose own sub-index is 62. 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 18 µg/m³, 1.2 times the WHO 24-hour guideline of 15 µg/m³; PM10 is 25 µg/m³ against a guideline of 45; ozone is 47 µg/m³ (below the WHO 8-hour level of 100); nitrogen dioxide is 13 µg/m³ (below the 24-hour guideline of 25).
Also this hour: carbon monoxide 215 µg/m³.
NASA FIRMS shows 5 fire hotspots within 300 km in the last day (nearest about 229 km), but particle levels are not elevated enough to point to smoke right now.
Zagreb AQI forecast: next 48 hours
Over the next 24 hours the AQI is forecast to range from 55 around Mon 4:00 pm to 62 around Sun 7:00 pm, staying "Moderate" throughout.
The following day looks similar, averaging about 62.
| Local time (Europe/Zagreb) | US AQI | Category | PM2.5 µg/m³ | PM10 µg/m³ | Ozone µg/m³ |
|---|---|---|---|---|---|
| Sun 7:00 pm | 62 | Moderate | 17.8 | 25 | 47 |
| Sun 10:00 pm | 61 | Moderate | 21 | 28 | 48 |
| Mon 1:00 am | 59 | Moderate | 9.1 | 11 | 54 |
| Mon 4:00 am | 58 | Moderate | 9.3 | 11 | 50 |
| Mon 7:00 am | 57 | Moderate | 12.2 | 15 | 40 |
| Mon 10:00 am | 56 | Moderate | 10.8 | 15 | 57 |
| Mon 1:00 pm | 56 | Moderate | 4.4 | 8 | 75 |
| Mon 4:00 pm | 55 | Moderate | 7.5 | 13 | 65 |
| Mon 7:00 pm | 55 | Moderate | 23.9 | 34 | 39 |
| Mon 10:00 pm | 57 | Moderate | 29.7 | 41 | 32 |
| Tue 1:00 am | 59 | Moderate | 23 | 32 | 37 |
| Tue 4:00 am | 62 | Moderate | 15 | 22 | 35 |
| Tue 7:00 am | 63 | Moderate | 16.2 | 23 | 31 |
| Tue 10:00 am | 64 | Moderate | 12.7 | 20 | 54 |
| Tue 1:00 pm | 65 | Moderate | 9.7 | 15 | 67 |
| Tue 4:00 pm | 66 | Moderate | 12.8 | 21 | 65 |
| Tue 7:00 pm | 67 | Moderate | 27.4 | 42 | 32 |
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 Zagreb tomorrow
Between 6 am and 9 pm local time, the cleanest air tomorrow is forecast around 4:00 pm (AQI 55, Moderate) and the worst around 6:00 am (AQI 57). The difference across the day is small, so timing matters little.
Zagreb vs the rest of Croatia
Across 3 Croatia cities we track, the average US AQI right now is 43 (Good). Zagreb at 62 is 19 points worse than average.
It ranks 3 of 3 from cleanest to most polluted; the cleanest is Split (30) and the most polluted Zagreb (62).
For context, the median across 3,909 cities worldwide is 57.
Air quality in cities near Zagreb
| City | Distance | US AQI | Category | PM2.5 µg/m³ |
|---|---|---|---|---|
| Ljubljana | 117 km | 71 | Moderate | 12.6 |
| Graz | 145 km | 57 | Moderate | 17.3 |
| Zadar | 198 km | 38 | Good | 4 |
| Baja | 233 km | 56 | Moderate | 13.8 |
| Split | 259 km | 30 | Good | 6.8 |
| Vienna | 268 km | 33 | Good | 9.5 |
| Bratislava | 273 km | 51 | Moderate | 6.5 |
| Venice | 287 km | 45 | Good | 6.3 |
Model vs measured
The nearest measured PM2.5 reading is 4.8 µg/m³ from Sensor.Community (median of 3 sensors), centred about 7 km from the city centre. That is 13 µg/m³ below the model estimate of 18 µg/m³. Low-cost sensors can read high in humid air; reference monitors are more accurate but sparser.
Advice for sensitive groups
At 62, most people are fine outdoors. If you are unusually sensitive to PM2.5, keep long or intense workouts to the cleaner hours shown above.
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 Zagreb
Air quality elsewhere
Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS), Sensor.Community, NASA FIRMS.