Measured · mindful · safe

The light your body was built for.

SunMaxx turns sunshine into a number you can trust, using established photobiology research. Track the vitamin D you make, know your burn limit before you reach it, and find the safest windows to step outside.

Start your first soak iOS
0
IU today
Your daily dial
Every ray, counted toward your goal.
2.840
IU today
Goal 5.000 · 57%
2.840
Today
UV 3
Now
42m
Burn
Gentle on your eyes
Catch the soft light, skip the glare.

SunMaxx finds the golden windows, when the sun is low and UV stays under 2, and guides a calm, timed gaze that never asks you to strain.

◷ Suggested gaze · up to 60s at a time
A bolder ritual
Sun on the skin, for hormones.
Alchemical illustration of a figure basking beneath the sun Safe countdown
  • Sun on the skin can raise testosterone. A 1939 study saw a marker rise nearly 200%.
  • Works for men and women. Needs strong midday UV.
  • SunMaxx counts you down and stops you before you burn.
Before you soak
Know your sweet spot, and your limit.
Type III · Light olive · Tans gradually UV 6 · midday · 20 min exposure
Face & Hands
~400 IU
Tee & Shorts
~1.250 IU
Shirtless
~2.150 IU
Swimwear
~3.150 IU
Fully bare
~3.950 IU
½ MED · Sweet spot
3.150 IU
1 MED · Burn dose
7.750 IU
Map of San Francisco showing your saved sun spots
Save your favourite sun spots
Pin the places you soak, right in the app
☀️Ocean Beach ☀️Presidio ☀️Dolores Park ☀️Embarcadero
▮▮ Map

Step outside. Soak smarter.

The oldest source of light there is. Measured, mindful, and safe.

Every number is built on peer-reviewed photobiology. Real dose-response science, not a gimmick.

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