A Dark Spot on the Sole of Your Foot

What a dark spot on the sole usually turns out to be

Most dark spots on the sole are not cancer. The usual causes are a bruise or blood blister from pressure, dried blood trapped inside a callus, a plantar wart studded with tiny clotted vessels, ground-in dirt, or an ordinary mole or freckle that has been there for years. The majority of pigmented spots on the foot turn out to be harmless. The catch is that none of these can be told apart from an early melanoma by sight alone — which is exactly why a spot that persists or changes gets examined rather than assumed.

Common harmless explanations include: - A bruise or blood blister — pressure or a knock pools blood under thick sole skin, which can look black or deep purple. - Talon noir, or "black heel" — pinpoint bleeding from friction, common in runners and court-sport players. - A plantar wart — often speckled with small black dots, which are clotted capillaries rather than pigment. - A callus with trapped debris — ground-in dirt or material can mimic a dark spot. - A mole, freckle, or lentigo — stable pigment that has not changed in a long time.

Why a spot on the sole gets extra attention

The sole, the palm, and the skin under the nails are exactly where one type of melanoma tends to appear. Melanoma can grow on skin that rarely sees sunlight, and when it shows up on the palms, soles, or nail beds it is called acral lentiginous melanoma 1Ref 1National Cancer Institute (PDQ Adult Treatment Editorial Board) (2025).Melanoma Treatment (PDQ®)–Health Professional Version.Melanoma can arise on non-sun-exposed acral skin (palms, soles, nail beds) as acral lentiginous melanoma, which is proportionally the most common melanoma subtype in people with darker skin.. It is proportionally the most common melanoma subtype in people with brown and black skin 1Ref 1National Cancer Institute (PDQ Adult Treatment Editorial Board) (2025).Melanoma Treatment (PDQ®)–Health Professional Version.Melanoma can arise on non-sun-exposed acral skin (palms, soles, nail beds) as acral lentiginous melanoma, which is proportionally the most common melanoma subtype in people with darker skin., so not burning in the sun is no reason to dismiss a foot spot — skin cancer in skin of color often appears on these very sites. Because few people expect cancer on the bottom of a foot, a melanoma on the foot is easy to overlook and is frequently found later and larger than one on an arm. Melanoma caught while it is still confined to the skin is far more survivable than melanoma that has spread 2Ref 2National Cancer Institute, Surveillance, Epidemiology, and End Results (SEER) Program (2025).Cancer Stat Facts: Melanoma of the Skin.Five-year relative survival for melanoma is much higher when the cancer is caught while confined to the skin than after it has spread to distant sites., so an early, honest look is worth it.

This is the same reason a dark spot on the palm of the hand, a spot between the toes that won't heal, or a new pigmented streak under a toenail all deserve the same attention. Acral melanoma does not respect the assumption that skin cancer only happens on sun-exposed skin.

The warning signs — reading ABCDE on the foot

Dermatologists use a checklist called ABCDE to decide whether a pigmented spot should be examined: Asymmetry, Border that is irregular or notched, Color that varies within the spot, Diameter larger than a pencil eraser, and Evolving — any change in size, shape, color, or texture over weeks to months 3Ref 3Tsao H, Olazagasti JM, Cordoro KM, et al. (2015).Early detection of melanoma: reviewing the ABCDEs.The ABCDE criteria (Asymmetry, Border irregularity, Color variegation, Diameter greater than 6 mm, Evolving) are the clinical features used to flag a pigmented lesion for examination.. On the sole, the E matters most: a bruise grows out and fades as new skin forms, while a melanoma tends to persist, enlarge, or darken. A single one of these melanoma warning signs is reason enough to have a spot looked at — you do not wait for all five. One ABCDE feature is enough to justify an exam; the checklist flags spots to check, it does not diagnose or clear them.

Bruise or melanoma — track it, don't guess

You cannot diagnose this at home, but you can gather what a clinician needs. Photograph the spot in good light beside a ruler or a coin for scale, and write down the date. A true bruise or blood blister usually follows a remembered injury, drifts toward the toes, and fades over a few weeks as the skin grows out. A spot you cannot tie to any injury — or one that is still there, or larger, after that — is worth having examined rather than watched forever. Soles are hard to inspect on yourself, so a mirror or a second set of eyes helps, and it is worth checking both feet, between the toes, and the nails while you are looking. Photograph it with a date and something for scale, and have it seen if it does not clearly grow out like a bruise.

How soon to be seen, and what the visit involves

A new or changing pigmented spot on the sole is worth a dermatology visit without long delay — weeks, not months. The clinician examines it, often with a dermoscope, a handheld magnifier that reveals patterns the naked eye misses. If it looks suspicious, the answer comes from a biopsy: the spot is sampled and examined under a microscope, because that is the only way to confirm or rule out melanoma 4Ref 4Swetter SM, Tsao H, Bichakjian CK, et al. (2019).Guidelines of care for the management of primary cutaneous melanoma.Melanoma is diagnosed by biopsy, with excisional or narrow-margin biopsy preferred to measure tumor thickness; thickness guides staging, and sentinel lymph node biopsy is considered for thicker tumors.. For a suspected melanoma, guidelines favor removing the whole lesion — an excisional or narrow-margin biopsy — rather than shaving off the top, so its depth can be measured accurately 4Ref 4Swetter SM, Tsao H, Bichakjian CK, et al. (2019).Guidelines of care for the management of primary cutaneous melanoma.Melanoma is diagnosed by biopsy, with excisional or narrow-margin biopsy preferred to measure tumor thickness; thickness guides staging, and sentinel lymph node biopsy is considered for thicker tumors.. That depth, or thickness, is the strongest single predictor of what treatment and follow-up look like, and for thicker tumors a sentinel node biopsy may be offered to check whether cells have reached the nearest lymph nodes 4Ref 4Swetter SM, Tsao H, Bichakjian CK, et al. (2019).Guidelines of care for the management of primary cutaneous melanoma.Melanoma is diagnosed by biopsy, with excisional or narrow-margin biopsy preferred to measure tumor thickness; thickness guides staging, and sentinel lymph node biopsy is considered for thicker tumors..

Getting a foot spot checked — photos, telederm, and screening

A clear photo can start the process. Teledermatology — sending images to a dermatologist, or meeting by live video — is a genuine front door, and the specialty maintains image-quality and security standards for it 5Ref 5American Academy of Dermatology (2024).Teledermatology Standards.Teledermatology (store-and-forward images and live video) is delivered under AAD image-quality and security standards and can be used to triage a skin concern.. It is a fast way to be triaged, though a spot that needs a biopsy will still require an in-person visit. One common point of confusion is worth settling: a national task force concluded the evidence is insufficient to recommend routine whole-body skin-cancer screening for adults who have no symptoms 6Ref 6US Preventive Services Task Force (2023).Skin Cancer: Screening.The USPSTF found insufficient evidence to recommend routine whole-body visual skin-cancer screening in asymptomatic adults; this addresses screening, not evaluation of a symptomatic or changing lesion.. That finding is about screening healthy skin — it does not apply to a spot you are already worried about, which counts as evaluation, not screening, and is exactly what a visit is for.

How soon is "soon," and how to keep watch

A pigmented spot on the sole is not a same-day emergency, and panic is not the goal — but "not an emergency" is not the same as "ignore for a year." The honest tempo is weeks: long enough to photograph and see whether it behaves like a bruise, short enough that a real melanoma is caught while it is thin and treatable. Between visits, many people keep a dated photo and compare it monthly, and check the other foot, the toes, and the nails at the same time. Anything that grows, changes color, bleeds, or refuses to heal moves the timeline up. If you are unsure whether what you are seeing has changed, that uncertainty is itself a good reason to have it examined.