Understanding your result
How to use it
Lighter skin and higher UV both mean you need stronger protection and burn faster. As a rule, use at least SPF 30 when the UV index is 3 or above, and SPF 50 for very fair skin or intense sun. Reapply every two hours, and after swimming or sweating — no sunscreen lasts all day.
⚕️ A general guide only. "Safe time" is a rough estimate; UV varies by location, altitude, reflection and cloud. Seek shade at midday and cover up — sunscreen is one layer of protection, not the only one.
Questions
What SPF should I use daily?
SPF 30 is a sensible everyday minimum when UV is 3+. Very fair skin or strong sun warrants SPF 50.
Does higher SPF last longer?
Not really — all sunscreen should be reapplied every ~2 hours. Higher SPF blocks slightly more UVB, it doesn't extend wear time.
Sources
Evidence-based · last reviewed July 2026