Warts are small, rough, fleshy bumps caused by the human papillomavirus (HPV). The most reliable way to identify one is by its texture and a telltale visual clue: tiny black dots scattered across the surface, which are actually clotted blood vessels inside the growth. Here’s how to recognize different types and tell them apart from other skin bumps.
What a Common Wart Looks Like
Common warts are the type most people picture. They show up as small, grainy, flesh-colored bumps, most often on the fingers and hands. They feel rough to the touch, almost like a tiny piece of cauliflower. Their surface is raised and dome-shaped, with an irregular texture that distinguishes them from smooth moles or cysts.
The single most useful feature for identifying a wart is the “black dots” pattern. If you look closely, you’ll often see a sprinkling of dark pinpoints across the bump. These aren’t seeds or dirt. They’re tiny blood vessels that have clotted inside the wart. Not every wart shows them clearly, but when they’re present, they’re a strong indicator you’re dealing with a wart rather than something else.
Another helpful test: warts disrupt the natural skin lines on your hands and feet. If you look at a callus or corn, your fingerprint lines continue right through it. A wart interrupts those lines. The normal ridges of your skin stop at the wart’s edge and pick up again on the other side.
Plantar Warts on the Feet
Plantar warts grow on the soles of your feet, and because you walk on them, they get pushed inward rather than growing outward like common warts. This makes them look flatter and harder, sometimes resembling a callus. You might notice a thick patch of skin with a well-defined border, and the same pinpoint blood vessel pattern visible when you look carefully. They can be painful with pressure, feeling like you’re stepping on a pebble.
Flat Warts Are Easy to Miss
Flat warts look nothing like the rough, bumpy warts most people expect. They’re smooth, slightly raised, and tiny, each about the size of a pinhead (1 to 5 millimeters across). Some are barely noticeable to the eye. They can be round or oval and tend to match your skin color or appear slightly pink or yellowish-brown.
These warts favor the face, the backs of the hands, the neck, and areas where skin gets nicked during shaving. In men, they often cluster along the beard area. In women, the legs are a common spot. One characteristic that sets flat warts apart is that they tend to appear in groups, sometimes dozens at a time, rather than as a single isolated bump. If you suddenly notice a cluster of tiny smooth bumps in a shaved area, flat warts are a likely explanation.
Warts Around and Under Nails
Periungual warts cluster around the fingernails or toenails and can be tricky to identify because they don’t always look like a classic wart. They present as firm, rough, yellow-brown or flesh-colored bumps that may merge into a larger cauliflower-like mass around the nail. They can crack and become sore, especially if they press against the nail bed.
The deceptive part is what’s happening underneath. A wart that looks small on the surface may extend under the nail plate, where a much larger portion of the growth is hidden. If the skin around your nails is thickening, cracking, or lifting the nail edge, a periungual wart could be the cause.
Genital Warts Look Different
Genital warts appear as small lumps in the anal and genital areas. They can show up alone or in clusters that resemble cauliflower. Their color often matches the surrounding skin or runs slightly darker, and they can feel either firm or soft. They’re caused by different strains of HPV than the ones responsible for hand and foot warts.
Skin tags in the genital area can look similar, since both can be skin-colored or darker. The key difference is structure: skin tags hang from a narrow, fleshy stalk (called a peduncle), giving them a dangling appearance. Warts sit directly on the skin without a stalk and have a broader, flatter base. If you’re unsure, a professional exam can distinguish the two quickly.
How Warts Differ From Similar Bumps
Several other skin growths can be confused with warts. Knowing the differences helps you figure out what you’re looking at.
Molluscum contagiosum is another viral skin infection, but the bumps look distinctly different. Molluscum lesions are smooth, firm, and round with a small dimple or dent in the center. Warts have an irregular, rough surface and no central dimple. If the bump looks like it has a tiny belly button in the middle, it’s more likely molluscum than a wart.
Corns and calluses form from friction and pressure, not a virus. They preserve your normal skin lines (fingerprint ridges pass right through them), while warts interrupt those lines. Corns and calluses also lack the black-dot blood vessel pattern.
Moles are usually smooth, evenly colored, and symmetrical. They don’t have the rough, grainy texture of a wart. A mole that changes shape, color, or size warrants attention for different reasons entirely.
How Long Before a Wart Appears
HPV doesn’t cause a wart immediately after you’re exposed. The virus can sit quietly in the skin for weeks or even several months before a visible bump develops. This long incubation period means you often can’t trace exactly where or when you picked it up. You might have walked barefoot at a pool months ago, or shaken hands with someone who had a wart weeks back. The delay between exposure and the first visible growth is completely normal.
Once a wart does appear, it can stay the same size, grow slowly, or occasionally multiply into a cluster. Some warts resolve on their own as your immune system clears the virus, but this can take months to years.
Signs That Need Professional Evaluation
Most warts are harmless and manageable, but certain situations call for a closer look. A bump that’s growing rapidly, looks like an open sore, or bleeds easily should be examined by a dermatologist, who may take a small tissue sample to rule out other conditions. The same applies if a growth is changing in color or shape, hurts, itches, or burns.
Warts on the face or genital area are worth having professionally evaluated rather than treating on your own, since the skin in those areas is more sensitive and the stakes of a wrong self-diagnosis are higher. If you have many warts appearing at once or a weakened immune system from any cause, professional guidance helps ensure the right approach. And if you’ve been treating a bump at home for weeks without progress, it may not be a wart at all.