Is the air in Phnom Penh safe today?

For most people, yes. Right now the US AQI in Phnom Penh is 53, which counts as moderate. Acceptable. Unusually sensitive people should ease off long, intense outdoor effort.

When is the best time to be outside in Phnom Penh?

Sat 02:00–5:00. That is the cleanest stretch in the next 24 hours, with the US AQI averaging about 44. The worst hour is around Sat 22:00, at 68.

What is the main pollutant in Phnom Penh?

Fine particles (PM2.5). It drives the index right now, at 10 µg/m³. Tiny particles from combustion, fires and dust that reach deep into the lungs. The main driver of AQI worldwide.

How does Phnom Penh's air compare with the WHO guideline?

Within the guideline. Over the next 24 hours PM2.5 averages about 11 µg/m³, against the World Health Organization's 24-hour guideline of 15 µg/m³. O3 is forecast above its guideline level.

How many cigarettes is a day of Phnom Penh's air?

About 0.5 cigarettes. Over the next 24 hours PM2.5 averages about 11 µg/m³. By Berkeley Earth's rule of thumb, 22 µg/m³ breathed for a day is roughly one cigarette.

Will air quality in Phnom Penh improve this week?

Today looks cleanest. Its AQI peaks at 68, against 115 on Tuesday, the worst day in the forecast.

Phnom Penh air quality

Cambodia · Live AQI and hourly forecast for the next 5 days · valid Sat 00:00 local time

Moderate

US AQI, mostly PM_2.5

Model estimate. Nearby measurements are shown separately.

Acceptable. Unusually sensitive people should ease off long, intense outdoor effort.

Next 24 hours: 43–68US AQI, highest around Sat 22:00
Best time outside: Sat 02:00–5:00US AQI about 44
PM_2.5 vs WHO guideline: 0.8×11 µg/m³ over 24 h, guideline 15
Cigarette equivalent: ≈ 0.5 a dayBerkeley Earth rule of thumb

Loading the live globe…

The live globe, centred on Phnom Penh. Switch pollutants, drag through the next 5 days or press play. Full map →

Pollutants in Phnom Penh right now

Pollutant	Now	Level	Next 24 h vs WHO
Fine particles PM_2.5	10 µg/m³	Moderate	0.8×
Coarse particles PM₁₀	10 µg/m³	Good	0.3×
Nitrogen dioxide NO₂	8.0 µg/m³	Good	0.3×
Ozone O₃	62 µg/m³	Good	1.1×
Sulphur dioxide SO₂	3.6 µg/m³	Good	0.1×
Carbon monoxide CO	286 µg/m³	Good	0.1×
Aerosol optical depth	0.30	Whole atmosphere · dimensionless
Desert dust	0 µg/m³	Modelled surface dust
UV index	0	Low

“Next 24 h vs WHO” compares the forecast with the World Health Organization’s 2021 guideline levels: 24-hour means of 15 µg/m³ for PM_2.5, 45 for PM₁₀, 25 for NO₂, 40 for SO₂ and 4 mg/m³ for CO, and 100 µg/m³ over 8 hours for ozone. Above 1× is above the guideline. Levels follow the US AQI, which is far less strict than the WHO, so air rated Good can still be above a guideline.

Next 48 hours

Hourly US AQI. Highest 77 around Sun 06:00, lowest 38 around Sun 16:00.

Good 0–50Moderate 51–100Sensitive 101–150Unhealthy 151–200Very unhealthy 201–300Hazardous 301+

5-day air quality forecast for Phnom Penh

Daily range of the hourly US AQI, from lowest to highest, on a scale of 0 to 150.

Day	US AQI	At worst	Worst hour	PM_2.5 avg	UV max
Sat 14 Nov	43–68	Moderate	22:00	11	8 Very high
Sun 15 Nov	38–77	Moderate	6:00	14	7 High
Mon 16 Nov	52–69	Moderate	19:00	14	7 High
Tue 17 Nov	63–115	Sensitive	11:00	19	9 Very high

Common questions about the air in Phnom Penh

Is the air in Phnom Penh safe today?
For most people, yes. Right now the US AQI in Phnom Penh is 53, which counts as moderate. Acceptable. Unusually sensitive people should ease off long, intense outdoor effort.
When is the best time to be outside in Phnom Penh?
Sat 02:00–5:00. That is the cleanest stretch in the next 24 hours, with the US AQI averaging about 44. The worst hour is around Sat 22:00, at 68.
What is the main pollutant in Phnom Penh?
Fine particles (PM_2.5). It drives the index right now, at 10 µg/m³. Tiny particles from combustion, fires and dust that reach deep into the lungs. The main driver of AQI worldwide.
How does Phnom Penh's air compare with the WHO guideline?
Within the guideline. Over the next 24 hours PM_2.5 averages about 11 µg/m³, against the World Health Organization's 24-hour guideline of 15 µg/m³. O₃ is forecast above its guideline level.
How many cigarettes is a day of Phnom Penh's air?
About 0.5 cigarettes. Over the next 24 hours PM_2.5 averages about 11 µg/m³. By Berkeley Earth's rule of thumb, 22 µg/m³ breathed for a day is roughly one cigarette.
Will air quality in Phnom Penh improve this week?
Today looks cleanest. Its AQI peaks at 68, against 115 on Tuesday, the worst day in the forecast.

Measured near Phnom Penh

Station and measurements	Distance	US AQI	Level
Unnamed sensor OpenAQ, low-cost sensor PM_2.5: 8.0 µg/m³ · Sat 00:00	9.2 km	44	Good
Unnamed sensor OpenAQ, low-cost sensor PM_2.5: 8.2 µg/m³ · Sat 00:00	15 km	46	Good

Air quality near Phnom Penh

US AQI right now. Cleanest nearby: Bangkok (76); worst: Hanoi (207). The tick on each bar is Phnom Penh, at 53.

Ho Chi Minh City 203 km SE 86 Moderate
Bangkok 539 km NW 76 Moderate
Kuala Lumpur 1,002 km S 88 Moderate
Chiang Mai 1,026 km NW 90 Moderate
Hanoi 1,058 km N 207 Very unhealthy
Yangon 1,111 km NW 91 Moderate

All 162 cities →

About this forecast

Forecast from CAMS global via Open-Meteo: the Copernicus Atmosphere Monitoring Service (CAMS) model at about 40 km resolution (about 10 km inside Europe). Global runs update every 12 hours and European runs every 24 hours. Models smooth out street-level peaks, so busy roads and industrial sites can be worse than shown. Nearby station measurements are independent observations, not adjustments to the forecast. The point forecast uses Open-Meteo’s CAMS products, including a separate carbon monoxide product; it can differ from the globe’s global grid. The AQI rates each hour on the US EPA scale, the same way the map colors it; official daily figures average over 24 hours (8 for ozone), so they can read lower after a short peak. Readings for 11.56°N, 104.93°E, valid 2026-11-13 17:00 UTC.