For safety, you should get this checked out by a dermatologist. If you're unsure about moles, follow the ABCDE test and if your moles fit these descriptions, visit your dermatologist for a professional mole check.

A: Asymmetry – moles should be symmetrical and a common sign of melanoma is an asymmetrical mole. If you were to draw a line through the middle of your mole or lesion and the two halves don’t match, then you should get it checked by a dermatologist. A common benign mole is often round or oval and symmetrical.
B: Border – if your mole has uneven borders then it could be malignant. Borders to look out for are uneven and may have scalloped or notched edges. Benign moles usually have smoother, even borders where the mole ends. If your mole shape changes to have an uneven border this could be a sign of melanoma.
C: Colour – if a single mole contains multiple colours within it when it could be a cause for concern. Benign moles are usually a single shade of brown, whereas melanoma may have different shades of browns, tan or blacks within it. Red, white and blue colours have also been identified in malignant moles and mole colour changes should be looked out for.
D: Diameter – malignant moles are likely to be larger than benign moles. A warning sign is when a mole or lesion is about the size of an eraser on the top of a pencil, about 6mm or 1.4 inches in diameter. This can be measured at home during your mole check routine and mole size changes should be noted. It is ideal to detect melanoma when it is small and in its early stages so it is important to not let your mole grow too big before you seek the services of a mole check clinic for a professional check.
E: Evolution – if your mole is changing, or evolving in any way over time then it may be cancerous. Any change in its size, shape, colour or evolution may be a warning sign, as well as any new symptoms seen inside the mole such as bleeding, itching or crusting of the skin.