howmuchsun

Vitamin D from sunlight in Vietnam

How long you need in the sun to make vitamin D, and when the sun is too low to make any at all, for 7 cities in Vietnam.

CityLatitudeElevationVitamin D winter
Ho Chi Minh City 10.82°N 7 m none
Hanoi 21.02°N 10 m none
Haiphong 20.86°N 12 m none
Cần Thơ 10.04°N 3 m none
Huế 16.46°N 8 m none
Da Nang 16.07°N 11 m none
Biên Hòa 10.94°N 6 m none

How these dates are calculated