Vitamin DGlobal Solar Explorer

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DAILY CURVE · · 9 Jul
0:003:006:009:0012:0015:0018:0021:0024:000°15°30°45°60°
45°
Vitamin D Estimate(theoretical clear sky — no weather data for this date)
5 minto synthesize 1000 IU
Best hour: 12:00 (UVI 10.8)
UV Window: 8:00 – 17:00
Time per hour (min for 1000 IU)
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
≤15 min≤30 min>30 min
Theoretical estimate with clear sky (no clouds or real data). Real weather data only covers ~14 days.
9 Jul
Vit D Hours:
0h → 10h+Vit D Limit

Frequently asked questions

Dive into the science behind the app

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The Sun and Vitamin D

Why solar angle, UV index, and glass all matter

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Sun vs Supplement

How solar synthesis compares to oral vitamin D

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Supplementing Well

Cofactors, timing, food sources, and dose

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The Sun Beyond Vitamin D

Nitric oxide, circadian rhythms, mood, and immunity

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See all questions →
Astronomical calculations + real UV data (Open-Meteo). Vitamin D estimation based on Holick/Dowdy (2010). Map: Natural Earth. Search: OpenStreetMap Nominatim. Threshold 45° (in vitro) / 50° (conservative).
Built by Javier Aguilar