Those pebble-like bumps with tiny black dots—especially on toes, soles, or fingers—are most often warts caused by the human papillomavirus (HPV). The black specks are clotted capillaries, a hallmark sign. On feet they’re called plantar warts; they can feel like a stone in your shoe and often hurt when you squeeze the sides.

How they spread

• Virus enters through micro-cuts in skin.
• Common in locker rooms, pools, showers, and sweaty shoes.
• Spreads by direct contact or from picking/filing the wart and touching other skin.

What to do (and not do)

• Do keep the area clean and dry; cover with a bandage or tape; wear flip-flops in communal wet areas.
• Don’t pick, cut, or shave over them—this spreads infection and can scar.
• Avoid sharing towels, socks, nail tools.

Home treatment options

• Salicylic acid (17–40%) pads/liquid: soak skin 5–10 min, gently pare dead skin, apply daily for several weeks.
• Cryotherapy kits can help small, recent warts, though office freezing is stronger.
• Duct tape occlusion is low-risk; evidence is mixed but sometimes helpful.

When to see a clinician

• Painful, spreading, bleeding, or uncertain diagnosis.
• If you have diabetes, poor circulation, are immunocompromised, or the wart is on the face/genitals.
• If no improvement after 6–8 weeks of proper home care.

Early care plus good foot hygiene usually clears them, and protects the people around you from catching HPV, too.