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The Sun Protection Factor (SPF) shown on a sunscreen label ranges from as low as SPF 2 to as high as SPF 100 and refers to that product’s ability to screen or block out the sun’s harmful rays. For example, if you use a sunscreen with an SPF 15, you can be in the sun 15 times longer that you would’ve been able to be in the sun, without any sunscreen whatsoever, before burning.

  • SPF protection does not increase proportionally. SPF 50 is not 2x as good as SPF 25.
  • SPF of 2 will absorb 50% of UV rays; SPF 15 absorbs 93%; SPF 30 absorbs 97%.


  1. Broad spectrum sunscreen, like Sunforgettable, provides protection against BOTH UVA and UVB rays. SPF numbers only cover UVB rays but both UVA and UVB cause aging and cell changes that can lead to skin cancer over time. If you don’t choose a ‘broad spectrum” sunscreen, you are basically missing the point entirely!

How It


There are two types of sunscreens – chemical absorbers and physical blockers. Learn why physical blockers are recommended.

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UVs come from the sun in three different wavelengths – UVA, UVB and UBC.
UVA and UVB matter the most to humans.

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