Plantar warts are hard, grainy growths that usually appear on the heels or balls of your feet, areas that feel the most pressure. This pressure also may cause plantar warts to grow inward beneath a hard, thick layer of skin (callus).
Plantar warts are caused by the human papillomavirus (HPV). The virus enters your body through tiny cuts, breaks or other weak spots on the bottom of your feet.
Most plantar warts aren't a serious health concern and may not require treatment. But plantar warts can cause discomfort or pain. If self-care treatments for plantar warts don't work, you may want to see your doctor to have them removed.