Higher SPF does not necessarily mean better protection.
"Most of the sunscreens we tested provided less protection than the SPF listed on the container," said Sue Booth with Consumer Reports.
You'll also see the words broad spectrum on many sunscreens.
"Broad spectrum means sunscreens are supposed to protect not just against UVB rays, but UVA rays as well," Booth said.
Both types of rays can cause skin cancer, and UVA rays can wrinkle and age your skin.
Consumer Reports' lab tests performed both on people and on test plates coated with sunscreen found some products offer better protection than others for both UVA and UVB rays.
It has six sunscreens to recommend. Top-rated is Up & Up Sport Broad Spectrum SPF 50 spray from Target.
"Spray sunscreens are convenient, but the risks of inhaling them are still being studied. So we don't recommend spraying children. And don't spray directly on your face," said Booth.
If you prefer a lotion, Consumer Reports named Equate Ultra Protection Sunscreen Broad Spectrum SPF 50 from Walmart a best buy. It offers better protection than several sunscreens tested that cost much more.
The other sunscreens in the top six include Coppertone Water Babies SPF 50, Walgreens Continuous Spray Sport and Hawaiian Tropic Sheer Touch 30 and Coppertone Sport High Performance SPF 30.
Consumer Reports says one more note of caution about sprays -- they are flammable. So wait for the spray to dry before going near an open flame.
With any sunscreen, you should apply sunscreen 15 to 30 minutes before you head into the sun and reapply it after you take a swim or every two hours.