Know Your ABCDEs

Melanoma 101 Understanding Melanoma Moles Know Your ABCDEs

What are the ABCDE’s of Melanoma?

Examine your skin regularly, looking for any new moles or lesions as well as changes in the moles you already have. When you examine your moles, remember the ABCDEs of melanoma. If you notice any of the following, consult your healthcare provider immediately.

ABCDEs of Melanoma

A = Asymmetry

Melanomas are frequently asymmetrical: the shape of one half does not match the other.

B = Border

Melanomas frequently have uneven or irregular borders (ragged or notched edges).

C = Color

Melanomas often contain multiple shades of brown or black but can sometimes be mixed with white, gray, blue, or red. Some melanomas will show a loss of color in a preexisting mole or in the area surrounding the mole.

D = Diameter

Melanomas are often larger than 6 mm (1/4 inch) in diameter. However, with increased awareness about early detection, about 30% of melanomas are found when they are less than 6 mm in diameter.

E = Evolution

Any change: Melanomas typically have shown some evidence of change in the months prior to diagnosis.

NOTE: The ABCDEs are different for children.  Read about the ABCDEs for children.

The “Ugly Duckling”


An “Ugly Duckling” is a mole or lesion that is unlike the others on your skin. It might be a lighter colored or darker colored mole or lesion than the others around it, or it might be a larger or smaller mole or lesions than others around it. If you have an Ugly Duckling, show it to your healthcare provider and keep your eyes out for other different looking moles and lesions.