Spots on your skin can appear for dozens of reasons, and the most likely explanation depends on their color, texture, and where they show up. The vast majority of skin spots are harmless, caused by sun exposure, normal aging, minor infections, or leftover marks from inflammation like acne. Some, however, signal conditions worth monitoring or treating. Understanding what different spots look like and why they form can help you figure out what you’re dealing with.
Dark Spots and Hyperpigmentation
Dark spots are among the most common skin concerns, and they all share one basic mechanism: your skin produces too much melanin (its natural pigment) in a localized area. What triggers that overproduction varies quite a bit.
Sun spots (solar lentigines): These flat, brown or tan spots appear on skin that gets the most sun exposure: your face, hands, forearms, and shoulders. They develop from years of UV exposure causing pigment-producing cells to multiply in a small area. Most people start noticing them in their 30s or 40s, and they become more common with age.
Post-inflammatory hyperpigmentation (PIH): If you’ve had acne, a cut, a burn, or any skin irritation, the healing process can leave behind a dark mark. Inflammation triggers your skin to ramp up melanin production at the injury site. These spots are flat, irregularly shaped, and sit exactly where the original irritation was. PIH is especially common in people with darker skin tones (generally Fitzpatrick skin types III through VI) and can take months or even years to fade on its own without treatment.
Melasma: This type of hyperpigmentation forms larger, symmetrical patches rather than small spots, usually on the cheeks, forehead, or upper lip. It’s strongly linked to hormonal changes during pregnancy or from oral contraceptives, though sun exposure makes it worse. Melasma can be stubborn and tends to recur even after treatment.
Freckles: These small, light brown spots appear in childhood after sun exposure and are most common in people with fair skin. They’re genetic, completely harmless, and often fade in winter when UV exposure drops.
Red or Pink Spots
Red spots typically involve blood vessels rather than pigment, which is why they can look so different from brown or white spots.
Cherry angiomas: These are small, bright red, dome-shaped bumps made of clusters of blood vessels. They’re extremely common and become more frequent with age. The exact cause isn’t fully understood, but aging, hormonal shifts (including pregnancy), and genetics all play a role. Cherry angiomas are completely benign. They don’t turn into anything dangerous, though they can bleed if scratched or irritated.
Post-acne redness (post-inflammatory erythema): After a pimple heals, it can leave behind a flat red or pink mark instead of a dark one. This happens because inflammation dilates tiny blood vessels in the skin, and that dilation persists after the breakout clears. These red marks are most noticeable in lighter skin tones and typically fade faster than dark post-acne spots, though they can still linger for weeks or months.
Petechiae: These are tiny, pinpoint red or purple dots caused by broken capillaries under the skin. They don’t blanch (turn white) when you press on them. Common causes include straining (from vomiting, coughing, or heavy lifting), certain medications, or minor injuries. A few petechiae from straining are usually nothing to worry about, but a sudden, widespread crop of them can indicate a blood clotting issue and warrants prompt medical attention.
White or Light-Colored Spots
Tinea versicolor: This is one of the most common causes of white or light-colored patches, especially on the shoulders, back, and upper chest. It’s caused by an overgrowth of a yeast that naturally lives on your skin. The fungus interferes with normal pigmentation, creating small, round patches that can appear white, pink, light tan, or yellow depending on your skin tone. The patches often have a fine, dry, scaly texture and tend to become more obvious after sun exposure, because the affected skin doesn’t tan with the rest of your body. Over time, individual patches can merge into larger areas. Antifungal treatments clear the infection, but the color difference can take weeks or months to even out afterward.
Pityriasis alba: Common in children and teenagers, this condition causes pale, slightly scaly patches, usually on the face, upper arms, or neck. The spots often start as faintly red or pink before fading to lighter than the surrounding skin. It’s considered a mild form of eczema and resolves on its own, though it can take months. Under a UV light, the borders of pityriasis alba patches appear blurry, which helps distinguish it from other conditions.
Vitiligo: This autoimmune condition causes the immune system to destroy melanin-producing cells, resulting in sharply defined white patches. Unlike tinea versicolor, vitiligo patches are completely smooth (no scaling) and tend to appear symmetrically on both sides of the body. It can develop at any age and may spread over time.
Raised, Bumpy, or Textured Spots
Seborrheic keratoses: These are among the most common benign skin growths in adults over 50. They look like waxy, slightly raised, oval bumps that seem “stuck on” to the skin’s surface. They can be brown, black, tan, or white, and they often appear on the face, chest, back, and shoulders. Seborrheic keratoses tend to grow larger and thicker over time, sometimes reaching about an inch across. They can look alarming, but they’re completely harmless and never become cancerous.
Actinic keratoses: These feel rough and scaly, often like sandpaper. They appear on sun-exposed areas such as the face, scalp, ears, neck, arms, and hands. Unlike seborrheic keratoses, actinic keratoses can become cancerous over time, which is why dermatologists typically recommend treating them. They’re usually smaller than 2 centimeters and may be the same color as your surrounding skin, pink, tan, or gray. Sometimes you’ll feel one before you see it. They can itch or burn slightly.
When a Spot Could Be Skin Cancer
Most skin spots are benign, but certain features should prompt a closer look. The widely used ABCDE criteria from the National Cancer Institute describe what to watch for in a mole or pigmented spot:
- Asymmetry: One half doesn’t match the other.
- Border irregularity: The edges are ragged, notched, or blurred, or pigment seems to spread into the surrounding skin.
- Color variation: The spot contains multiple shades of brown, black, tan, or areas of white, gray, red, pink, or blue.
- Diameter: The spot is larger than 6 millimeters (about the size of a pencil eraser), though melanomas can be smaller.
- Evolving: The spot has changed in size, shape, or color over recent weeks or months.
Beyond the ABCDE features, pay attention to any spot that bleeds without obvious injury, itches persistently, or looks noticeably different from all your other moles (the “ugly duckling” sign). A spot doesn’t need to check every box to be worth investigating. Any single concerning change, especially rapid growth or evolving appearance, is reason enough to have it evaluated by a dermatologist.
Figuring Out What Your Spots Are
Color is the single most useful clue for narrowing down what’s causing your spots. Brown or dark spots usually involve excess pigment from sun damage, hormones, or past inflammation. Red spots point to blood vessel changes. White spots suggest either lost pigment or a fungal infection interfering with your skin’s coloring. Rough or scaly texture in a spot, especially on sun-exposed skin, raises the question of actinic keratosis.
Your skin tone also affects how spots appear. Tinea versicolor looks white or light tan on darker skin but pinkish on lighter skin. Post-acne marks tend to show up as dark spots in deeper skin tones and red marks in lighter ones. Actinic keratoses may blend with the surrounding skin color in darker complexions, making texture a more reliable sign than color.
Location matters, too. Spots on the shoulders and back suggest tinea versicolor. Spots on sun-exposed areas like the face, hands, and forearms point toward sun damage. Symmetrical patches on both sides of the body are characteristic of vitiligo. Spots that line up exactly with a previous rash, burn, or breakout are almost certainly post-inflammatory marks.
If you have a spot that’s been stable in size, shape, and color for months or years, it’s very likely benign. Spots that are new, changing, or symptomatic (painful, bleeding, itching) deserve a professional evaluation, even if they turn out to be nothing serious.