Many of us have moles on our bodies, and for the most part, these moles are nothing more than harmless spots of pigment on our skin. However, for some of us, these moles can quickly turn malignant. Knowing how to quickly and accurately identify a mole to tell if it’s harmless or cancerous could save your life or the life of someone you care about. Please keep reading to learn more about dangerous moles and to learn how to visually confirm whether or not your mole falls into this high-risk category.

What Does a Dangerous Mole Look Like?

Moles (also known as “nevi”) are extremely common, and most of us can have anywhere between ten to fifty of these clusters of pigment cells on our bodies. Comprised of “melanocytes, ” these can be either congenital (were present when you were born) or acquired (appeared throughout your lifetime). Moles often appear in areas exposed to sunlight, such as your back, face, and neck. To learn more about neck moles, click here.

The first key to recognizing a dangerous mole is to know what type of mole is not dangerous. It’s important to remember, however, that even a benign mole can become cancerous later on, so be mindful of any changes to even common, typical moles.

  1. Common (Typical) Moles:

    Examples of Common Moles

    Examples of Common Moles

    Most people have typical moles on their skin and, unless they change in appearance, should not be concerning.

    • Smaller than a pencil eraser (5mm or less).
    • Has even borders.
    • Smooth in appearance.
    • Brown, tan, or pink.
    • Usually just one color.
    • Round or oval in shape.
  2. Dysplastic (Atypical) Moles:

    These moles pose a higher risk because they are more likely to become cancerous. Be extremely careful to monitor these for changes.

    • Larger than a pencil eraser (5mm or greater).
    • Jagged, uneven borders.
    • Pebbly or scaly in appearance.
    • Black, blue, pink, or dark brown.
    • Can be several different colors.
    • Amorphous (not round or oval) in shape.

    Atypical moles (dysplastic nevus)

The more dysplastic nevus you have, the greater your risk is for developing skin cancer. People who do have five or more of these atypical moles are ten times more likely to get melanoma when compared to people who do not have any dysplastic nevi.

Dangerous Moles in Pictures

While cancerous moles typically show up in places where sun exposure occurred, it would be a deadly mistake to assume that places that are covered do not form cancerous masses. Melanoma can literally appear anywhere on your body – your face, your backside, your fingernails, the bottoms of your feet, and even inside your eyes…nowhere is safe from this aggressive type of cancer.

Important Information:
When you can’t avoid the sun, you must take precautions to reduce your risk of sun damage and cancer. A lot of people mistakenly assume that because they use a little bit of sunblock, they should be fine and well-protected. The fact is, you need about a shot-glass full (over 1 ounce) of broad-spectrum SPF 30 or greater to properly protect yourself. For areas of your body where you cannot apply sunblock, wear UV-rated protective clothes, hats, and eye-wear.
  1. Your Face
    Dangerous mole on faceAs you can see by the large size and uneven border, this cancerous mole grew considerably before the patient sought treatment for it. The face is a vulnerable place to forming malignant moles, but sunblock and avoiding sun exposure during peak daytime (10:00 a.m. to 2:00 p.m.) can help protect you. Click here to learn more about facial moles.
  2. Your Feet
    Foot melanomaMalignant moles can even form on the bottom of your feet. Note the dark, uneven color and jagged borders. This type of melanoma is the variety that forms on darker-skinned persons.
  3. Your Hair
    Dangerous mole in hairMany people mistakenly believe that dangerous moles cannot form on your scalp, but these can grow unchecked. The large, uneven shape and scaly appearance are a big clue to the dangerous nature of this mole. Wear a hat when you’re outside to help protect your head from cancer.
  4. Your Fingernails
    Dangerous mole under fingernailYou can tell by the dark color and uneven shape that this mole (also known as “subungual melanoma”) is dangerous. Remember, cancerous moles can form in surprising places, so be sure to check your toenails, too.
  5. Your Eyes
    Dangerous mole in eyeEven the eyes are vulnerable to dangerous mole growth. These are hard to detect, which is why regular eye appointments are so important. The large, bulbous shape and uneven color are a hint that this mole is cancerous. Use UV-blocking glasses and sunglasses when you go outside to help protect your eyes.
  6. Your Buttocks
    Dangerous mole on buttocksThis malignant mole was found on the upper thigh, by the buttocks. It is identified by its uneven color, borders, and raised appearance. Click here to learn more about raised moles. Check your entire body to be certain cancerous moles aren’t growing undetected.


Did you know that the majority of melanomas are found not by doctors, but by regular people just like you? That’s why scheduling regular skin checks are so important; knowing your own body and the subtle changes to moles could be life-saving.

Some things that may look like skin cancer, but aren’t, include:

  • Warts,
  • Skin tags,
  • Cherry angiomas,
  • Seborrheic keratoses.

If you’re concerned about cherry angiomas, then click here to learn more about these small, red bumps on your skin.

Who needs to perform regular skin checks?

  • People with fair skin and score lower on the Fitzpatrick Skin Type Scale.


  • People with a history of skin cancer in their family.
  • People who have five or more dysplastic moles.
  • People with more than 50 common moles.
  • People who spend a lot of time in the sun.
  • People who have a history of severe, blistering sunburns.
  • People with congenital melanocytic nevi.
Dark-skinned people are also at risk for melanoma.

Most people would benefit from a skin check every six months, but if you fall within a demographic that is at elevated risk, you should check every month. Regular appointments with your dermatologist could also be beneficial, as they can help you track changes to your skin. Enlist the help of a family member, significant other, or a close friend to help you monitor your moles and alert you of any sudden changes.

How to Tell if a Mole is Dangerous

A harmless mole can appear to be malignant, and a malignant mole can sneak under the radar and seem harmless. The number one factor you should consider is change. If a mole seems different than before, then that’s a significant indicator that it has become cancerous.

Sometimes changes can be gradual, but they can also be abrupt and seemingly overnight. If caught early, skin cancer has a 95% survival rate. However, melanoma is highly aggressive and can develop roots and spread to vital organs in as little as just a few weeks.

Knowing your ABCDEs can make the difference between early detection and waiting too long to get treatment.

Know your ABCDE’s of melanoma skin cancer

ABCDE's of melanoma

Report any and all changes to your skin to your dermatologist or physician right away. If they suspect that you have melanoma, they can order a biopsy to determine if your mole is cancerous or benign.

Halo Moles: Are They Dangerous?

Moles that have a white ring, or halo, around them are called “halo moles”. They occur when your body’s immune system decides that your mole is dangerous and must be attacked. This causes the skin around the mole to fade and appear paler when compared to your normal skin.

Halo neviA halo mole has these characteristics:

  • Usually tan, brown, or pink in color.
  • Shows up anywhere on the body, but most often on back, chest, or stomach.
  • Most often appears in younger people (children and young adults).
  • You can have several at one time.
  • They can go away on their own.
  • Aren’t itchy or painful.

While the presence of halo mole doesn’t always mean you’ll get cancer, they do occasionally turn cancerous. You’ll need to take extra steps to protect yourself with sunblock and routine skin checks to prevent this from happening.

Moles can go from innocent to lethal in no time flat, which is why regular skin checks are so key in preventing melanoma from spreading. If you fall within a high-risk group, please learn how to identify common, dysplastic, and cancerous moles. This knowledge could save your life, or the life of your loved ones.

You can find further details of Types of moles here.