howmuchsun

Vitamin D from sunlight in Switzerland

How long you need in the sun to make vitamin D, and when the sun is too low to make any at all, for 3 cities in Switzerland.

CityLatitudeElevationVitamin D winter
Zürich 47.37°N 429 m 8 Oct – 14 Mar (158 days)
Geneva 46.20°N 400 m 12 Oct – 10 Mar (150 days)
Basel 47.56°N 279 m 7 Oct – 15 Mar (160 days)

How these dates are calculated