Three small growths that get confused constantly, largely because people try to tell them apart by colour — which is the one property that varies most between individuals and skin tones, and therefore the least useful.
Texture and location do far better.
Touch it before you look at it
This single test resolves most cases.
A skin tag is soft. It gives when you press it, and it often hangs from a narrow stalk so that it moves independently of the skin around it. Sizes run from about two millimetres up to a few centimetres.
A wart is firm. It sits raised off the skin with a rough, slightly hardened surface, more like a callus than a growth. Pressing it does not squash it.
A mole is usually flat, or only slightly raised, and it is continuous with the skin rather than sitting on top of it. It is round or oval, and its colour is even throughout.
Soft and dangling, hard and rough, flat and even. That is most of the work done.
Then look at where it is
Location is the second-best clue, because all three have strong preferences.
Skin tags grow where skin rubs. The neck, particularly where a collar or a chain sits. The underarms. The groin. The eyelids. Under the breasts. Along the sides, abdomen and back. If a growth is in a fold or a friction point, that is a skin tag pattern.
Warts favour hands and feet. They are caused by the human papillomavirus, so they can appear elsewhere and can spread to other parts of your own skin by contact — but hands and feet are where they turn up most.
Moles appear on skin that gets sun. They range from pink through light brown to very dark brown depending on your skin tone, and most people acquire theirs in childhood and early adulthood.
What about colour?
Use it last, and use it carefully.
Skin tags are usually the same colour as the rest of your skin or slightly darker, and some go pink or red when irritated. Moles are typically a different colour from the surrounding skin, evenly so. Warts are usually close to skin tone with a roughened surface.
The trouble is that every one of those descriptions shifts with skin tone, lighting and how recently the thing was rubbed by a waistband. Colour is worth noting mainly as a baseline — so that a change in colour later is something you can recognise.
The distinction that actually matters
Whether a growth is a skin tag, a wart or a mole is much less important than whether it is changing.
The American Academy of Dermatology publishes the warning signs as the ABCDEs: Asymmetry, where one half does not match the other. Border that is irregular, ragged or blurred. Colour that is uneven or has more than one shade. Diameter, with larger growths meriting more attention. And Evolving — any change in size, shape, colour or height, or a growth that starts to itch, bleed or crust.
Evolving is the one to hold on to. A stable growth that has looked the same for a decade is reassuring whatever it is. A growth that is doing something new is worth showing someone this month, whichever of the three you believe it to be.
The same goes for anything that looks unlike your other moles, and for a new growth appearing after about the age of forty.
When it is none of the three
A fair number of people arrive at this comparison because they have something that is not a skin tag, a wart or a mole at all. Four others come up constantly.
Seborrhoeic keratoses are the most commonly mistaken for moles, and they are extremely common from middle age onwards. They are waxy, slightly raised and often described as looking stuck on to the skin rather than growing out of it, in shades from pale tan to almost black. They are harmless. They are also the growth people most often panic about, because a dark, irregular-looking patch appearing in your fifties is exactly what everyone has been told to watch for.
Cherry angiomas are small, bright red, smooth dots — usually a millimetre or two, often on the trunk. They are collections of tiny blood vessels, they are harmless, and they bleed impressively if you catch one with a razor.
Molluscum contagiosum produces small firm pearly domes with a tiny dimple in the centre. Painless, spread by skin contact, and in adults often passed on sexually. They resolve on their own but can take months.
A cyst is deeper, smooth, and moves slightly under your finger rather than sitting on the surface. Weeks to months rather than days, and it will not respond to anything you put on it.
None of that list is a reason for alarm. It is a reason not to be confident that you have narrowed something down to three options when there are considerably more than three.
How a dermatologist actually tells
Largely by looking, often with a dermatoscope — a magnifier with a light that shows structures under the surface of the skin that are invisible to the naked eye. That is why the identification takes seconds rather than minutes, and why it is so much more reliable than the comparison you can do in a mirror.
If anything about a growth is uncertain, the next step is a biopsy: a small sample, or the whole growth, sent to be examined properly. That is a routine thing rather than an escalation, and it is the reason not to destroy a growth at home — a lesion that has been burned or cut at is harder to identify, and there may be nothing left to examine.
What to skip and why
Diagnosing by image search. Photographs flatten texture, which is the property that actually separates these, and they misrepresent colour on every screen.
Using wart remover on a skin tag. Wart treatments are formulated for hard tissue. A skin tag is soft, so the medication goes past it into the skin around it and leaves irritation or a scar with the tag still attached.
Treating a mole at home. Never. Not with a kit, not with a remover, not with anything. Beyond the injury risk, destroying a mole removes the evidence a dermatologist would have used.
Removing anything you have not had identified. The whole reason to bother telling these apart is that a small number of skin cancers are mistaken for benign growths, and that mistake is only costly in one direction.
Waiting to see whether a changing growth settles down. Change is the signal. Waiting is what turns an easy appointment into a harder one.
When to see a dermatologist
Anything asymmetric, irregularly bordered, multi-coloured, growing, itching, bleeding or crusting. Anything that looks unlike the rest of your moles. Anything new in middle age. And anything you simply cannot identify with confidence.
None of that means something is wrong. It means the question is cheap to answer properly and expensive to guess at, and a dermatologist generally answers it in the first few seconds of looking.
| What | How it looks and feels | Where and how long |
|---|---|---|
| WhatSkin tag | How it looks and feelsSoft, skin-coloured or darker, often on a narrow stalk | Where and how longNeck, underarms, groin, eyelids, under the breasts · 2mm–5cm |
| WhatWart | How it looks and feelsFirm, raised, rough surface | Where and how longMost often hands and feet · caused by HPV · can last months or years |
| WhatMole | How it looks and feelsUsually flat, round or oval, evenly coloured | Where and how longSun-exposed skin · pink through to dark brown depending on skin tone |
| WhatAny of them, changing | How it looks and feelsNew, growing, changing colour, itching or bleeding | Where and how longGet it looked at — this is the one distinction that matters |
Texture is the most reliable single test you can do yourself. Soft and dangling points to a skin tag; hard and rough points to a wart. Colour is the least reliable, because all three vary with skin tone.
Go deeper on this
- How to remove skin tagsSkin tag removal is a two-minute clinical procedure. Here is what each method involves, how billing actually works, and why at-home kits are the wrong idea.
- Skin tag removal at the dermatologistWhat a skin tag removal appointment actually involves, from booking to aftercare, how many you can have done at once, and how the billing works.
Questions people ask
- How can I tell a skin tag from a wart?
- Touch it. A skin tag is soft and often hangs off the skin on a narrow stalk. A wart is firm, sits raised off the surface and feels rough, almost like a small area of hardened skin. Location helps too — warts turn up most often on hands and feet, skin tags in folds where skin rubs against skin.
- Can a skin tag turn into a mole, or a mole into cancer?
- A skin tag does not become a mole; they are different structures. Moles are extremely common and the overwhelming majority stay harmless for life, but a small number can change, which is why the advice is to watch for change rather than to worry about moles in general.
- Are warts contagious?
- Yes. Warts are caused by the human papillomavirus and can spread by contact, including to other parts of your own skin. Skin tags and moles are not contagious. If a growth has appeared in several places over a few months, that pattern fits a wart rather than a skin tag.
- Do warts go away on their own?
- Often, eventually. Without treatment warts can last months or years, which is why people treat them rather than wait. Skin tags do not resolve on their own, and moles are permanent unless removed.
- Which of these can I treat at home?
- Wart treatments exist over the counter and are designed for hard tissue. Skin tags should not be removed at home, and using wart remover on one damages the surrounding skin without removing the tag. Moles should never be treated at home under any circumstances.
- What if I genuinely cannot tell?
- Then that is the answer — go and have it looked at. Telling these apart takes a dermatologist seconds, and the reason to bother is not the skin tag or the wart. It is that a small number of skin cancers get mistaken for both.
What this article is based on
10 named sources, linked in full. No "studies show".
- NHS
- NHS
- NHS
- American Academy of Dermatology
- American Academy of Dermatology
- American Academy of Dermatology
- American Academy of Dermatology
- American Academy of Dermatology
- NHS
- NHS