Common Nevus
Also known as: Normal Mole, Melanocytic Nevus, White Moles on Skin
Normal moles - clusters of pigment cells. Usually harmless, but monthly monitoring for changes is essential.
What to look for
Side-by-side comparison
Normal mole
Round, stable, even color
Changing mole
Any change = see a doctor
A common nevus is a normal mole - a well-defined growth formed by a cluster of melanocytes (pigment-producing cells). Most adults develop between 10 and 40 common moles by their 30s, and the number gradually decreases with age as some moles naturally fade.
Normal moles are typically smaller than 6mm, round or oval, symmetrical, evenly colored (tan, brown, or flesh-toned), and have smooth, well-defined borders. They can be flat or raised, and may darken with sun exposure or during pregnancy due to hormonal changes.
The clinical importance of common moles lies in two facts. First, having more than 50 common moles is an independent risk factor for melanoma - roughly doubling the average risk. Second, while most melanomas arise as new growths, about 20-30% develop within a pre-existing mole. This is the reason monthly self-examination using the ABCDE rule is recommended for everyone.
The key to monitoring moles is looking for change. A mole that has looked the same for years is almost certainly benign, regardless of its size or color. A mole that is changing - growing, darkening, developing irregular borders, or producing new symptoms - deserves evaluation.
Quick self-check
Does this look like common nevus? Answer 2 questions.
Is the mole symmetrical, round, and evenly colored?
Has it changed in any way recently?
The ABCDE Rule — Visual Guide
The screening method dermatologists recommend for self-examination.
Asymmetry
One half does not match the other half
Normal
Both halves match
Warning
Halves don't match
Border
Edges are irregular, ragged, or blurred
Normal
Smooth, well-defined edge
Warning
Ragged, blurred edges
Color
Multiple colors or uneven color distribution
Normal
One uniform color
Warning
5+ colors mixed
Diameter
Larger than 6mm — about the size of a pencil eraser
Normal
Under 6mm
Warning
Over 6mm (pencil eraser)
Evolution
Any change in size, shape, color, or symptoms over time
Normal
No change over 12 months
Warning
Grew, darkened, irregular
Most important: Evolution (E) is considered the single most critical criterion. Any mole that is changing — in size, shape, color, or producing new symptoms like itching or bleeding — should be evaluated by a dermatologist regardless of other features. This guide is for screening only.
Risk factors
- Genetic predisposition (number of moles is largely hereditary)
- Sun exposure during childhood and adolescence
- Fair skin
When to see a dermatologist
- ⚠Any mole that changes in size, shape, or color
- ⚠A mole that begins to itch, bleed, or crust without being injured
- ⚠You have more than 50 moles (increased melanoma screening recommended)
- ⚠A new mole appearing after age 40 (less common and deserves attention)
Often confused with
Not sure if this is common nevus? Compare:
Want a more detailed check?
Our full ABCDE checker evaluates 5 clinical criteria in 30 seconds.
Full ABCDE check →Frequently asked questions
How many moles is normal?
Most adults have 10-40 common moles. The number is largely genetic, peaks in the 30s-40s, and gradually decreases with age. Having more than 50 is a risk factor for melanoma.
Can a normal mole turn into melanoma?
About 20-30% of melanomas arise within pre-existing moles, but most of moles never become cancerous. The key is monitoring for changes - a stable mole is almost certainly safe.
Should I have moles removed just in case?
Prophylactic removal of normal-looking, stable moles is not recommended. It would not significantly reduce melanoma risk (since most melanomas arise as new growths) and would result in unnecessary scarring.
Related conditions
Dysplastic Nevus
Atypical moles with irregular features. The single strongest visual risk marker for melanoma.
Melanoma
The most dangerous skin cancer - but 99% survival when caught early. Learn the ABCDE signs.
Halo Nevus
A mole surrounded by a white ring of depigmented skin. The immune system attacking the mole - usually benign, most common in teenagers.