Hello, I was just googling lump on top of head and this site came up... I have a painless lump on the top of my head, and it feels like it is under the skull. It s in the center, and it s about an inch in diameter. Also, there is an indentation, about the size of a nickle, in front of it, directly where the fontanel would be, and another directly behind it. All three areas are perfectly aligned with the center of my skull. I m 43, female, about 175lb, and about 5 7 . I m perfectly healthy, and have been a very well-balanced vegetarian for over twenty years. Thanks so much. :)