Get smarter about the sun. UV Index Forecast tells you exactly when sunlight helps you make vitamin D and when it starts to harm your skin — with a live UV index, a personalized vitamin D timer, and sunburn alerts built around your skin type.
Most weather apps show a UV number and stop there. This app turns real-time UV index data into the two things that actually matter: vitamin D in, sunburn out. Whether you're planning a beach day, a long run, gardening, or just walking the dog, you'll know the safe time to be in the sun.
Built for people correcting low vitamin D, outdoor athletes, and anyone protecting fair or sensitive skin.
★ LIVE UV INDEX & FORECAST ★
• Real-time UV index with UVA and UVB levels for your exact location
• Hour-by-hour UV forecast from sunrise to sunset
• Full 7-day UV forecast with daily highs
• Color-coded UV scale (low to extreme) following the WHO standard
• Background that adapts to the current UV intensity
★ VITAMIN D TIMER ★
Stop guessing how long to stay outside. The vitamin D timer calculates your exact minutes of sun exposure to reach the ~1,000 IU daily reference intake, personalized to:
• Your Fitzpatrick skin type (I–VI)
• The current UV index at your location
• Sun elevation and time of day
• Bare-skin exposure (face, arms, legs)
When the timer ends, extra sun adds little vitamin D and only raises your sunburn risk — clear, science-based guidance.
★ SUNBURN CALCULATOR ★
• Sunburn time estimate — minutes until your skin reaches its burn threshold (minimal erythemal dose)
• Personalized to your skin type — fair skin gets stricter limits than darker skin
• SPF reminder when you push past your safe sun window
• Daily UV warnings to help you avoid the riskiest hours
• Supports responsible sun safety and skin cancer prevention habits
★ VITAMIN D NOTIFICATIONS ★
Never miss the best moment for vitamin D from the sun. Choose the alerts you want:
• Window opens — when the UV index first reaches the vitamin D synthesis threshold
• Best moment — peak UVB intensity, your shortest effective dose
• Last chance — the final viable hour for vitamin D before the sun drops too low
★ SKIN TYPE PERSONALIZATION ★
Pick your Fitzpatrick skin type once and every calculation adapts. From Type I (always burns, never tans) to Type VI (deeply pigmented). The same UV index means very different things for different skin — and this app respects that.
★ THE SCIENCE ★
Built on peer-reviewed dermatology and atmospheric research: the WHO / ICNIRP UV index scale, the Fitzpatrick skin classification, and established vitamin D and minimal-erythemal-dose exposure models. Your local UV forecast already accounts for ozone, altitude, and cloud cover — no rough regional estimates.
★ PRIVACY-FIRST ★
• Location is used only to fetch UV and weather data — never stored or shared
• No tracking, no profiles sold
• Skin type and settings stay on your device
★ PERFECT FOR ★
✓ Outdoor enthusiasts — runners, cyclists, hikers, climbers
✓ Beach lovers, surfers, swimmers, sailors
✓ Parents protecting children's sensitive skin
✓ Anyone correcting low vitamin D or vitamin D deficiency
✓ Fair-skin and sensitive-skin users
✓ Drivers, gardeners, and outdoor workers
✓ Travelers comparing the UV index between destinations
UV index forecast, vitamin D timer, sunburn calculator, sun exposure guide, sun safety app — everything in one clean, fast experience.
Download today and get the most out of every sunny day — safely.