TanMeter App Store

TanMeter tool

Calculate How Long You Can Stay in the Sun Safely

Enter your skin type, SPF used, and current UV index and TanMeter calculates the maximum minutes you can stay in direct sun before risking a burn.

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How it works

  1. Select your Fitzpatrick skin type in the TanMeter calculator.
  2. Enter the SPF level of sunscreen you are wearing.
  3. Confirm your location's current UV index or type a city.
  4. Read your safe exposure window in minutes before reapplication or shade.
  5. Start a TanMeter session timer to track elapsed sun time.

FAQ

Does safe sun time account for sunscreen already applied?

Yes. Enter your SPF and TanMeter extends safe minutes proportionally, but still recommends reapplication every two hours.

What if I am in the water or sweating?

Toggle the water-resistant mode and TanMeter shortens safe windows to account for SPF wash-off during swimming or heavy sweat.

Can I tan safely within the calculated time?

Safe sun time is the burn threshold, not a tanning target. TanMeter recommends shorter sessions with SPF to minimize skin damage.