UV Index Today

Real-time solar radiation monitoring

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Sunburn Time & SPF Calculator

Pick your skin type and UV index to estimate how long until unprotected skin may burn, plus a practical SPF recommendation. Estimates only — not medical advice.

Skin type

Fitzpatrick scale — choose the closest match

UV Index
Manual input
6.0
High
Type II · Fair

Adjust UV

Drag or type a UV value (0–20)

0816

Exact value

Unprotected

17 min

Estimated time to burn for Type II at UV 6.0 with no sunscreen.

Recommended SPF

SPF 50+

High UV — cover up, limit midday sun, and reapply after swimming or sweating.

With sunscreen

8h 20m

Theoretical window at SPF 30. Real protection is often lower if you apply too little.

Quick take: Fairly short unprotected window. Apply sunscreen before heading out. Reapply about every 2 hours, and sooner after swimming or heavy sweating.

How this calculator works

Burn-time estimates use a common planning formula: minutes ≈ (skin-type factor × SPF) ÷ UV index. Type II (fair) uses a factor of 100 minutes at UV 1 unprotected.

SPF multiplies that unprotected window in theory. In practice, most people apply less than the lab dose, so treat the protected time as an upper bound — not a guarantee.

Tips that matter more than the number

  • Use broad-spectrum sunscreen (UVA + UVB), not SPF alone.
  • Apply enough — roughly a shot-glass amount for full-body coverage on adults.
  • Reapply every 2 hours outdoors; after water or towel-drying, do it sooner.
  • Clothing, shade, and timing still beat sunscreen by itself at High UV and above.

This tool is for everyday sun-safety planning only. It does not diagnose skin conditions or replace dermatologist advice. UV varies by location, clouds, altitude, and reflective surfaces.