Is my mole dangerous? The ABCDE check
Five features that move a mole from something you dislike to something that should be examined this week.
Written and clinically reviewed by Dr. G. Revanth, MBBS DDVL DNB · August 2026 · 2 min read
Check any mole that is asymmetric, has an irregular or notched border, contains more than one colour, is larger than six millimetres, or has changed in any way — itching, bleeding, crusting or growing. Change over weeks rather than years is the single most important signal, and it outweighs all the others.
ABCDE
| What to look for | |
|---|---|
| A — Asymmetry | One half does not match the other. |
| B — Border | Irregular, notched, or blurring into the surrounding skin. |
| C — Colour | More than one shade, or a colour that has changed. |
| D — Diameter | Larger than six millimetres, or growing. |
| E — Evolving | Any change at all: itching, bleeding, crusting, growth. |
E is the one that matters most. A mole you have had, unchanged, for twenty years is far less concerning than one that has done something new in the last two months, whatever the other four letters say.
What ABCDE cannot do
It is a public-awareness checklist, not a diagnosis. It catches the classic presentations and it misses others — nodular lesions can be symmetrical and single-coloured, and some concerning lesions are under six millimetres. It is a threshold for getting looked at, not a substitute for looking.
What examination adds
- •Dermoscopy. A polarised lens that shows the pigment network below the surface. Structures invisible to the naked eye become measurable.
- •Comparison. Your other moles. A lesion that looks unlike all your others is more interesting than one that looks like a hundred of them.
- •Photography. Mapped and dated, so change can be measured rather than remembered.
- •Biopsy where indicated. Fifteen to thirty minutes, local anaesthetic, and a definitive answer in seven to ten working days.
What to do about a mole you are unsure of
Have it looked at. We would rather see you and find nothing — that is not a courtesy, it is how this is supposed to work. The skin assessment on this site takes two minutes and will tell you plainly whether what you are describing should wait.
If a lesion is bleeding, ulcerating, growing quickly, or changing month to month, do not use an online tool. Book.