How Much Sunscreen Do You Need—And Where?

ThinkstockWhen it comes to sunscreen, how much you use is just as important as when and what you apply. A swipe here and a dot there just won't cut it. "Most people only apply a percentage of the amount necessary, making an SPF 30 closer to an SPF 15," says New York dermatologist Dr. David Bank.

One ounce of sunscreen-the equivalent of a full shot glass-slathered from head to toe is what you should aim for.

So we tested the full one-ounce dose and calculated just how much needs to be applied (to each body part) to protect skin and beat the burn. Full disclosure: It was quite greasy. Allot considerable rubbing-in time.

MORE: NEW FDA Sunscreen Rules

Face

A penny-sized dollop of broad-spectrum sunscreen is what is needed to shield your face from damage. Don't forget the hairline, hair part, the tops of your ears and even your eyelids-some of the most delicate and oft-forgotten areas, according to Bank.

Neck and Décolletage

A dose about the size of two almonds fully protects this delicate area.

Arms and Hands

Use about two quarter-sized rounds of lotion, one for each arm. Be sure not to overlook the area under the arms and the tops of your hands.

MORE: Weatherproof Your Skincare

Stomach

A dollop the size of a maraschino cherry provides ample coverage for your midsection.

Back and Shoulders

Measure out a squeeze of sunscreen roughly equivalent to the size of three mini marshmallows to completely cover this burn-prone area.

Legs and Feet

Two half dollar-sized blobs of sunscreen, one for each side, protects from your glutes on down.

If this seems like a lot of sunscreen for your body, it probably is. But it's crucial not to skimp to get the protection promised on the sunscreen bottle. Make sure to reapply sunscreen every two hours and after swimming or sweating.

MORE: Get Sunscreen Savvy!

If a classic eight-ounce tube of sunscreen retails for about $10, it's costing you $1.25 and about four minutes of your time on each of the eight applications-not a lot for two hours of protection and a lifetime of healthy skin.

Sunscreens Without The Slickness

Don't let the grease-factor keep you from protecting your most crucial asset-you. Try one of the new dry formulas that let you lube up without the slippery sensation.

Peter Thomas Roth Uber-Dry Suncreen SPF 30 $26

Neutrogena Ultra Sheer Dry-Touch Sunblock SPF 55 $9

Coola Face SPF 30 Cucumber Matte Finish $32

By Jolene Hart


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