UV TrackerUV in Vietnam and Southeast Asia: high all year
Why UV runs high year-round
Vietnam sits at a tropical latitude, roughly 8 to 23 degrees north, where the sun stays high in the sky for most of the year. Combined with abundant sunshine, high-to-very-high UV index readings are normal across most provinces — not just a summer phenomenon.
How the south and north differ
Southern provinces, closer to the equator, tend to hold a high UV index year-round with little seasonal swing. The north has a more pronounced seasonal pattern — UV drops in winter but still runs moderate to high on clear days, and climbs sharply again from late spring.
Hours to avoid
The general 10-to-4 rule still applies, but at this latitude the high-risk window tends to run longer than in temperate regions. The shadow rule — a shadow shorter than you are tall means UV is high — is a quick check that needs no meter. See the best and riskiest hours for sun for more.
Sun protection, Vietnamese-style
Long sleeves, wide hats, and the common practice of covering the face outdoors already provide substantial physical coverage — an effective protective layer. Sunscreen is still worth adding to exposed areas like the back of the hands, neck, and ears; see SPF, explained for how to use it correctly.
How long your skin can take it
Most Vietnamese skin falls into Fitzpatrick type III or IV. At a UV index of 8–11 — common around midday in the dry season across many provinces — type III has roughly 29 to 21 minutes of safe sun time, and type IV roughly 38 to 27 minutes. See the full tables by skin type or use the calculator for today's exact number.
Measure your actual sky
A province-wide forecast doesn't account for cloud cover, shade, or the specific environment where you're standing. UV Tracker's sky scan reads the sky right where you are, for a number closer to reality than a plain forecast.
UV Tracker measures the UV where you stand — sky scan for local conditions, one photo for your skin type, and your safe sun time on one card. Free forever.
References
- World Health Organization, Global Solar UV Index: A Practical Guide. Accessed 2026-09-01.
- World Meteorological Organization, guidance on the global UV index.
- Kosmopoulos PG, et al. "Real-time UV-Index retrieval in Europe using Earth Observation based techniques and validation against ground-based measurements." Atmospheric Measurement Techniques, doi:10.5194/amt-2020-506.
UV forecast data in the app: Open-Meteo.
This article is general information, not medical advice. Sun-exposure estimates are approximations. If you have concerns about your skin, or a history of skin cancer in your family, see a doctor or dermatologist.