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⏱️ Live UV Dose Timer

Track your accumulated UV dose in real time. Set your UV Index and skin type, then start the timer. Alerts fire at 50%, 75%, 90%, and 100% of your MED threshold.

Timer Settings

Settings are auto-populated from the Calculator page if you visited it first. You can also enter values manually below.

0.05 = face/hands, 0.35 = t-shirt+shorts, 0.80 = bikini/trunks

00:00
Press Start to begin

UV Dose Progress

Accumulated UV Dose 0% of MED
SED Accumulated
0.000
Time Remaining
Set UVI to calculate
Go to Calculator

How the Timer Works

  • Formula: SED/min = 0.015 × UV Index. The timer multiplies elapsed minutes by this rate to get accumulated SED.
  • Thresholds: Alerts fire at 50%, 75%, 90%, and 100% of your skin type's MED (Minimal Erythemal Dose).
  • Audio: A tone plays at each threshold (requires browser permission). Louder/higher tones for higher thresholds.
  • Important: The timer uses a fixed UVI. Real UV changes with clouds, shade, and time of day. Check the hourly chart on the Calculator page for context.
  • Read the full disclaimer →