Black spots under the feet: what to check

Pressure and the thick outer layer of sole skin can hide important details. Do not assume that every dark dot is dirt or a bruise, particularly when it appeared without a remembered injury or continues to change.

A dark area beneath a callus may be dried blood from friction, running, tight footwear, or stepping on something. Plantar warts can show pinpoint dark dots from tiny clotted vessels and may interrupt the normal skin lines. A splinter or other foreign material can leave a focal tender mark.

A flat pigmented patch may be a mole or another pigment change. Colour extending beyond an expected pressure area, an irregular outline, several colours, or progressive enlargement cannot be assessed reliably from appearance alone. Infection is more concerning when warmth, redness, drainage, or increasing pain surrounds a break in the skin.

Wash and dry the foot, inspect it under bright light, and compare it with the other sole. Photograph the spot beside a familiar object for scale, then reduce rubbing with well-fitting footwear. Leave the surface intact: cutting a callus, digging for a splinter, or using wart acid on an uncertain pigmented lesion can cause injury and delay diagnosis.

People with reduced foot sensation, poor circulation, diabetes, or immune suppression should arrange earlier professional foot care rather than attempting home removal. A dermatologist or podiatry clinician can pare thick dead skin safely when appropriate and inspect the structures underneath.

Book an examination if the spot is new without a clear cause, enlarges, changes colour or border, persists as an injury heals, or repeatedly bleeds. Prompt care is appropriate for severe pain, inability to bear weight, spreading redness, warmth, pus, fever, a deep puncture, or a suspected retained object. A rapidly worsening foot wound needs urgent attention, particularly when sensation or circulation is impaired.

Ask whether the mark lies in the surface skin or beneath it, whether normal skin lines cross the area, and whether magnified examination or a sample is appropriate. Mention recent footwear changes, sports, punctures, travel, foot numbness, and any change documented in photographs.