What do black marks on my fingernails mean? Little black areas have suddenly popped up on the ends of a number of my fingernails. They are like small black streaks in the direction of nail growth, about 1mm long. Looks very out of place having perfect jet black coloured marks on your nails, even though it's very small. They have appeared on all fingernails, but some fainter than others.
They are splinter hemmoraghes and are usually caused by some sort of trauma when they appear at the free edge and usually even at the cuticle. They are voids in the nail plate that fill up with blood from the underlying nail bed. They will grow out with the nail plate.