Many people first notice a new or odd-looking spot on their skin by accident, while putting on lotion or after a day outdoors. That small moment of noticing can matter more than you might think.

Quick summary: A skin self-exam is a simple, free check you can do at home in about ten minutes. Looking at your own skin once a month helps you learn what is normal for you, so you can spot changes early. Melanoma is a serious skin cancer, but when it is found early it is often easier to treat (Source: Cancer Research UK, 2024). This guide explains how to check your skin for melanoma, what the ABCDE rule means, the spots people often miss, and when to call a doctor.

Why checking your own skin matters

You see your own skin every day. That makes you the person most likely to notice a new spot, or a mole that is starting to change. A self-exam does not replace a doctor. It simply helps you catch changes sooner and bring them up early.

The most important warning sign of melanoma is a new spot, or a spot that is changing in size, shape, or color (Source: American Cancer Society, 2024). Skin cancer rates have grown over recent decades, which is one reason regular checks are encouraged (Source: WHO, 2016). Catching a change early gives you and your care team more options, and often means simpler treatment.

Who should be especially careful

Anyone can develop melanoma, but some people may be at higher risk. Talk with your doctor about more frequent checks if any of these apply to you:

• Fair skin that burns easily, light eyes, or red or blond hair
• A history of bad sunburns, especially in childhood
• Many moles, or moles that look unusual
• A personal or family history of melanoma or other skin cancers
• Use of indoor tanning beds
• A weakened immune system

Having a risk factor does not mean you will get melanoma. It simply means a regular skin check is an even more useful habit for you.

How often should you check your skin?

For most adults, a self-exam about once a month is a reasonable habit. The best time is after a bath or shower, in a room with good light (Source: American Cancer Society, 2024).

Doing it on the same day each month, such as the first of the month, makes it easier to remember. If you have many moles, a family history of melanoma, or have had skin cancer before, your doctor may suggest checking more often and seeing a skin specialist on a set schedule.

The ABCDE rule: what to look for

The ABCDE rule is a simple guide to the usual signs of melanoma. It helps you decide which spots to show a doctor (Source: American Cancer Society, 2024).

• A is for Asymmetry: One half of the spot does not match the other half.
• B is for Border: The edges are irregular, ragged, notched, or blurred.
• C is for Color: The color is not the same all over. It may include shades of brown or black, or patches of pink, red, white, or blue.
• D is for Diameter: The spot is wider than about 6 millimeters, roughly the size of a pencil eraser. Melanomas can sometimes be smaller, so do not ignore a small spot that is changing.
• E is for Evolving: The spot is changing in size, shape, or color. It may also start to itch, bleed, or crust (Source: Cancer Research UK, 2024).

There is one more clue worth knowing: the "ugly duckling" sign. This is a spot that simply looks different from the other moles around it. An ugly duckling spot may be worth a doctor's review even if it does not tick every ABCDE box (Source: American Cancer Society, 2024).

What a melanoma can look like

Melanomas do not all look the same, so it helps to know the range. Many appear as a new dark spot or a mole that is slowly changing. Some are flat, while others become raised or firm over time. The color is often uneven, with mixed shades of brown, black, or even pink and red.

Not every melanoma is dark. A small number can be skin-colored, pink, or red, which can make them easy to miss. This is why a changing spot deserves attention even when the color seems mild. A normal mole, by contrast, is usually one even color, has smooth borders, and stays about the same over months and years (Source: Mayo Clinic, 2024). The common theme across all of these is change: a spot that grows, shifts shape, or starts to itch or bleed is worth a closer look.

How to do a full skin self-exam, step by step

What you need

You only need a few simple things:

• A bright, well-lit room
• A full-length mirror
• A hand-held mirror
• Optional: a comb or hairdryer to part your hair, and a notebook or phone to track spots

The step-by-step check

Take your time and move through your whole body in the same order each time, so you do not skip an area (Source: American Cancer Society, 2024):

• Face the mirror and check your face, ears, neck, chest, and belly. If you have breasts, lift them to check the skin underneath.
• Check your underarms, both sides of your arms, the tops and palms of your hands, between your fingers, and under your fingernails.
• Sit down and check the front of your thighs, shins, the tops of your feet, between your toes, and under your toenails.
• Use the hand mirror to look at the soles of your feet, your calves, and the backs of your thighs, one leg at a time.
• Use the hand mirror to check your buttocks, genital area, lower and upper back, and the back of your neck and ears.
• Part your hair, with a comb or hairdryer, and check your scalp.

It can help to ask a partner or family member to look at hard-to-see areas, such as your back and scalp. The first check may take longer because you are mapping what is normal for you. After that, it usually goes quickly.

Do not forget the easy-to-miss spots

Melanoma can appear in places that rarely see the sun. It can develop under fingernails or toenails, on the palms of the hands, on the soles of the feet, and even in the eye (Source: Cancer Research UK, 2024). Mayo Clinic notes that hidden melanomas can occur in areas that are hard to see, which is why a full-body check matters (Source: Mayo Clinic, 2024).

This is important for people of every skin tone. In people with darker skin, melanoma more often appears on the palms, soles, or under the nails, so these areas deserve extra attention. A change under a nail, such as a new dark streak, is worth showing to a doctor.

Sun protection: lowering your risk every day

Self-exams help you find changes early, but daily habits can help lower risk in the first place. Most evidence suggests that changes in behavior, such as more outdoor activity and more intense sun exposure, are a major reason skin cancer rates have grown (Source: WHO, 2016).

Simple steps may help: seek shade in the middle of the day, wear a wide-brim hat and protective clothing, use sunscreen on exposed skin, and avoid indoor tanning beds. These habits are part of a broader set of lifestyle changes that can reduce your cancer risk, and they fit naturally alongside a monthly skin check. For a wider view of how everyday choices add up over time, you may also find our guide on how lifestyle choices impact cancer risk helpful.

Keeping track between checks

It can be hard to remember exactly how a mole looked last month. Some people take dated photos of spots they want to watch, using a coin or ruler beside the spot for scale. A simple body map or notebook can also help you record where spots are and whether they change.

Bring these notes and photos to your appointment. They can make the visit more useful and help your doctor see whether a spot has truly changed over time.

When to talk to your doctor

Contact your doctor or a skin specialist if you notice any of the following (Source: Mayo Clinic, 2024; Cancer Research UK, 2024):

• A new spot that looks different from your other moles
• A mole that is changing in size, shape, or color
• A spot that itches, bleeds, oozes, or will not heal
• A sore or mark that lasts several weeks without a clear cause
• Any new change under a nail, on a palm or sole, or in your eye

It is always okay to ask for a check, even if you are not sure. The earlier a melanoma is found, the easier it tends to be to treat, and the more likely treatment is to be successful (Source: Cancer Research UK, 2024). If you have many moles or a family history of skin cancer, ask your care team how often you should be seen.

This article is for general information and is not a substitute for medical advice. Always consult your oncologist or care team about your specific situation.