The short answer
A skin self-exam is when you look over your own skin to notice new or changing spots. The ABCDE rule helps you spot moles that might need a doctor's attention. Checking regularly helps you learn what is normal for you, so changes stand out. Report anything new, changing, or unusual to your doctor.
A skin self-exam means looking over your own skin to notice new or changing spots.
The ABCDE rule stands for Asymmetry, Border, Color, Diameter, and Evolving.
Checking regularly helps you learn what is normal for you, so changes are easier to catch.
Use good light, a full-length mirror, and a handheld mirror for hard-to-see areas.
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The full explanation.
The simple version
A skin self-exam is when you look over your own skin to check for new spots or changes in the ones you already have. You do not need special training or tools, just good light and a couple of mirrors.
The point is not to diagnose yourself. The point is to get to know your skin so you can notice when something looks different, and then tell your doctor.
Knowing what is normal for you is the whole idea.
The ABCDE rule for moles
Doctors use a simple set of letters to describe warning signs in a mole. If a spot has one or more of these, it is worth showing your doctor.
- A is for Asymmetry. One half of the mole does not match the other half.
- B is for Border. The edges are ragged, notched, or blurry instead of smooth.
- C is for Color. The color is uneven, or there is more than one color, such as brown, black, red, or white.
- D is for Diameter. The spot is larger than a pencil eraser (about a quarter inch), though some melanomas are smaller.
- E is for Evolving. The spot is changing in size, shape, color, or feel, or it is new.
Most moles are harmless. But a spot that fits several of these letters, or that simply looks different from your other spots, deserves a doctor's look.
A mole that stands out from the rest, sometimes called the "ugly duckling," is worth checking.
How to check your skin, step by step
Give yourself a few quiet minutes in a well-lit room with a full-length mirror and a handheld mirror.
- Face the full-length mirror and look at your face, neck, chest, and belly.
- Raise your arms and check both sides of your body, your underarms, and both sides of your arms.
- Look at the palms of your hands, between your fingers, and under your fingernails.
- Sit down and check your legs, the tops and bottoms of your feet, between your toes, and under your toenails.
- Use the handheld mirror to see the back of your legs, your buttocks, and your lower back.
- Use the handheld mirror, or ask someone you trust, to check your upper back, the back of your neck, and your scalp. Parting your hair helps you see the scalp.
Do not skip hidden spots; skin cancer can appear where the sun rarely reaches.
What is normal, and what is not
It is normal to have moles, freckles, and other marks, and to gain a few over the years. Most stay about the same. What matters is change and difference.
Call your doctor if you notice a spot that:
- Is new and looks unusual
- Is changing in size, shape, or color
- Has uneven edges or more than one color
- Itches, hurts, bleeds, oozes, or does not heal
- Simply looks different from your other spots
When in doubt, get it checked; catching a change early is what self-exams are for.
Making it a habit
A self-exam works best when it becomes routine. Many people check about once a month. Picking a regular day, like the first of the month, makes it easier to remember.
If it helps, take photos of any moles you want to track, so you can compare them over time. This is not a test you can fail. It is simply a calm, regular check-in with your own skin, and a way to know when it is time to call your doctor.
Words to know
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Common questions
▸How often should I check my own skin?
Many people find that checking about once a month works well. The goal is to check often enough to notice changes over time. Pick a regular time, like the first of the month, so it becomes a habit.
▸What is the ABCDE rule?
It is an easy way to remember warning signs in a mole: Asymmetry (one half looks different), Border (edges are ragged or blurry), Color (more than one color), Diameter (bigger than a pencil eraser), and Evolving (changing over time). A spot with these features is worth showing your doctor.
▸What if I find a spot that worries me?
Do not panic, but do not ignore it either. Most spots are harmless. Still, it is a good idea to have a new, changing, or unusual spot checked by a doctor. Only a doctor can tell for sure, sometimes with a biopsy.
▸Can I skip areas I cannot see easily?
Try not to. Skin cancer can appear in spots you might not think of, like the scalp, back, buttocks, soles of the feet, and between the toes. A handheld mirror or help from someone you trust can make these areas easier to check.
▸Do darker-skinned people need to check their skin too?
Yes. Skin cancer is less common in people with darker skin, but it can still happen, sometimes in less sun-exposed areas like the palms, soles, and under the nails. Everyone benefits from knowing their own skin.
▸Is a self-exam the same as a doctor's exam?
No. A self-exam helps you notice changes and decide when to call your doctor. A professional exam adds a trained eye and tools. The two work together.
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