Warts are small, rough skin growths that vary in appearance depending on their type and location. Most look like firm, grainy bumps with a rough texture, ranging from 1 millimeter to about 10 millimeters wide. Some are flat and barely visible, others are raised and bumpy, and a few grow in thin, finger-like projections. Here’s how to identify each type and tell them apart from other skin growths.
Common Warts on Hands and Fingers
Common warts are the type most people picture. They typically show up on the fingers and hands as rough, dome-shaped bumps that feel grainy or gritty to the touch. Most are round or slightly irregular, ranging from about 2 to 10 millimeters wide, roughly the size of a pencil eraser or smaller. They’re usually skin-colored, grey, or brownish.
The hallmark feature is tiny black or dark brown dots scattered across the surface. These are often called “wart seeds,” but they aren’t seeds at all. They’re small blood vessels that have clotted inside the wart. If you look closely at a common wart, you’ll see these pinpoint dots against a rough, slightly raised surface. Some warts develop a bumpy, cauliflower-like texture as they grow larger, especially when several cluster together.
Plantar Warts on the Feet
Plantar warts grow on the soles of your feet, usually on the ball or heel. Because you walk on them, they get pushed inward rather than growing outward, giving them a flattened, “pushed in” appearance. This makes them easy to confuse with calluses.
A few visual cues help you tell the difference. Plantar warts contain the same tiny black dots (clotted blood vessels) that common warts have. They also disrupt the natural lines of your skin. If you look at the ridges on the bottom of your foot, a callus follows those lines, but a plantar wart interrupts them. When multiple plantar warts merge together into a larger patch, they’re called mosaic warts. These can cover a wider area of the sole and look like a single rough plaque rather than individual bumps.
Flat Warts
Flat warts are the smallest and subtlest type. They measure between 1 and 5 millimeters across, no bigger than the head of a pin. Instead of being rough and raised, they have smooth, flat tops that barely rise above the skin surface. Their color tends toward yellow, brown, or pinkish, making them blend in more easily with surrounding skin.
What makes flat warts distinctive is their numbers. They almost always appear in clusters, sometimes 20, 50, or even 100 or more at a time. They commonly show up on the face, forehead, or legs. Because they’re so small and flat, people sometimes mistake them for a rash or skin irritation rather than warts.
Filiform Warts on the Face
Filiform warts look completely different from other types. Instead of a round bump, they grow as thin, finger-like or thread-like projections of skin, typically 1 to 2 millimeters long. They stick straight out from the skin surface, almost like tiny spikes or bristles. They’re skin-colored and most often appear around the eyes, lips, nose, or chin. Because of their narrow shape and prominent facial location, they tend to be the most cosmetically bothersome type, even though they’re usually small.
Genital Warts
Genital warts affect the moist tissues of the genital area and can look quite different from warts on the hands or feet. They often appear as small, soft, skin-colored bumps. When several grow close together, they can form a cauliflower-like cluster. Some are so small and flat that you can’t see them without close inspection. In people with weakened immune systems, they can occasionally multiply into larger clusters, but this is uncommon.
How Warts Differ From Moles and Skin Tags
A few simple visual features separate warts from other common skin growths. Warts are thick, rough, and sit deep in the skin. They feel hard and may have a scaly or callus-like texture underneath, even if the top surface appears somewhat smooth. They’re typically colorless or skin-toned.
Moles, by contrast, are brown or tan. The skin on a mole stays soft, and moles are generally round with smooth borders. They can be flat or raised, and they sometimes grow hair. Both moles and warts have a broad base and sit deep in the skin, but color is the easiest way to distinguish them.
Skin tags are entirely different in shape. They look like small flaps or balloons of skin hanging by a thin stalk. They dangle from the surface rather than sitting flush against it. Warts are broad-based and anchored firmly into the skin, while skin tags are soft, loose, and superficial.
When a Growth Might Not Be a Wart
Certain skin cancers, particularly squamous cell carcinoma, can resemble warts. A cancerous growth may appear as a thick, rough, scaly patch or a wart-like bump that crusts or bleeds. The key warning signs that separate a suspicious growth from a simple wart include bleeding that doesn’t stop, a sore that won’t fully heal over several weeks, rapid growth in size, irregular borders, and crusting that comes and goes. A growth with a raised edge and a lower, depressed center is also worth getting checked. Any skin bump that keeps changing, bleeding, or refusing to heal deserves a closer look from a dermatologist.