Brief Answer:
It looks like seborrheic keratosis

Detailed Answer:
Hello and welcome,

It looks like seborrheic keratosis, not melanoma. However, I'd suggest going in to have it checked because it is better to confirm by seeing it visually in person.

Here is an image of seborrheic keratosis: https://www.aad.org/public/diseases/bumps-and-growths/seborrheic-keratoses

They are usually dark brown and look like they've been pasted on rather than growing inside the skin. They are easily treated with liquid nitrogen. The doctor freezes it, in a few days it falls off completely, and the skin under it heals in and usually looks entirely normal.

It's good to have a general skin survey at least once a year, particularly if your underlying skin color is fair. Do go in and get it checked, but I don't think you have to worry.

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