Skin Tags vs Warts: How to Tell Them Apart

You found a small bump on your skin and you're trying to figure out what it is. Is it a harmless skin tag, or is it a wart that could spread? It's a common worry, and the good news is that telling them apart is usually straightforward once you know what to look for.

The short answer: a skin tag is soft, hangs from a thin stalk, and is not contagious. A wart is firmer, sits flatter against the skin with a rough, grainy surface, and is caused by a virus that can spread. Here's how to tell the difference and what to do about each.

What's the difference between skin tags and warts?

The biggest difference is the cause. A skin tag, known medically as an acrochordon, is simply normal skin. It's a soft growth made of loose collagen fibers and small blood vessels wrapped in ordinary skin, and it hangs from a thin stalk called a peduncle. Skin tags are not caused by a virus, are not contagious, and are not a sign of cancer.

Warts are different. They're caused by the human papillomavirus (HPV), and that makes them contagious. A wart can spread to other people through direct contact, and it can even spread to other spots on your own body, a process called autoinoculation. There are more than 100 types of HPV, and over 150 subtypes have been described in the dermatology literature.

How to tell a skin tag from a wart by looking

You can usually tell them apart by feel and appearance. Morphology, the shape and texture, is the clearest clue.

Here's a quick comparison:

• Skin tag: soft, flesh-colored or slightly darker, hangs from a thin stalk, smooth, usually 1 mm to a few mm (occasionally up to several cm).
• Wart: firm and grainy, sits flatter against the skin, rough or cauliflower-like surface, often with tiny dark dots.
• Skin tag location: skin folds such as the neck, armpits, and groin.
• Wart location: hands, fingers, knees, and the soles of the feet (plantar warts).

What causes each one?

Skin tags become more common with age, appearing more often after the fourth decade of life. They affect men and women about equally. They're also strongly linked to metabolic factors, including obesity, metabolic syndrome, type 2 diabetes, insulin resistance, dyslipidemia, and PCOS. If you're developing many skin tags, it can be worth discussing your overall metabolic health with a clinician, though the tags themselves are harmless.

Warts are caused entirely by HPV entering the skin, often through a small cut or break. They tend to show up on areas exposed to friction or shared surfaces, which is why plantar warts are common after walking barefoot in locker rooms and around pools.

How long do they last, and do they go away?

Skin tags don't resolve on their own. They tend to stay put unless they're removed.

Warts, on the other hand, often clear by themselves as your immune system catches up to the virus. Untreated common warts typically persist for 1 to 2 years before resolving. Here's what the research shows about spontaneous clearance:

• About two-thirds (roughly 67%) of warts clear on their own within two years.
• In children, about 50% clear within 6 months and around 90% within 2 years.
• Because of this, a wait-and-see approach is reasonable, especially in children.

How are skin tags and warts treated?

Skin tags don't need treatment for medical reasons. If a tag is bothersome, catches on clothing or jewelry, or you simply don't like how it looks, a clinician can remove it in the office. Avoid trying to cut or tie off a skin tag yourself, which can cause bleeding and infection.

For warts, the common over-the-counter approach is salicylic acid. It's applied once daily after soaking the wart in warm water, gradually layering the wart down over time, and is often covered with tape or a bandage between applications. When that isn't enough, a dermatologist can offer in-office options such as cryotherapy (freezing), electrocautery, laser, or photodynamic therapy. To avoid spreading warts, don't pick or bite at them, and wear sandals in locker rooms and on pool decks.

When should you see a doctor?

Most skin tags and warts are harmless, but it's worth getting a professional opinion in some situations. See a clinician if a growth bleeds, changes color, grows quickly, becomes painful, or you simply aren't sure what it is. A bump you assume is a skin tag or wart could occasionally be something else that deserves a closer look.

You should also see a dermatologist if a wart is on your face or genitals, spreads despite treatment, or is interfering with daily activities. A clinician can confirm the diagnosis and recommend the most effective option for your situation.