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Corns and calluses

Medically reviewed by Last updated on Oct 25, 2023.

What are corns and calluses?

Harvard Health Publishing

Corns and calluses are a thickening of the outer layer of skin. This thickening is known medically as hyperkeratosis. Corns and calluses develop as part of the skin's normal defense against prolonged rubbing, pressure and other forms of local irritation.

Corns and calluses

Symptoms of corns and calluses

On the feet, a small corn or callus may not cause any symptoms. However, a large, bulky corn or callus can cause foot pain and difficulty walking.

After prolonged irritation, a discolored area (brown, red or black) may develop under a large corn or callus. This discoloration is caused by a small amount of bleeding in the space between thick and normal skin. In severe cases, the thick and normal skin may separate, exposing the area to possible infection, especially in people with diabetes.

Diagnosing corns and calluses

Your health care professional probably will ask about your shoes, because shoes with narrow toes are more likely to cause corns. He or she also will ask about your foot history and your history of other medical problems, including diabetes and circulation problems. Some types of foot problems can alter the mechanics of the foot, causing abnormal pressure on certain areas and leading to calluses. Also, any previous surgery or trauma to the feet may affect the structure and alignment of foot bones, increasing the risk of calluses.

To assess whether your corns and calluses are related to foot abnormalities, your doctor will inspect your feet for toe deformities, structural problems of the bones, poor bone alignment and problems related to an abnormal way of walking (gait). If your doctor finds some abnormality during this part of the foot exam, he or she may suggest a specific type of padding or shoe insert to help prevent your corns and calluses from returning or causing as much discomfort.

Also, whenever there is a painful area of thickened skin on your feet, your doctor may need to check whether it is a plantar wart, a localized skin infection caused by human papilloma virus. The diagnosis can be made by shaving down the thickened skin and looking for tiny blood vessels at the base and a lack of normal skin ridges (as in a fingerprint), the hallmarks of a plantar wart.

Expected duration of corns and calluses

Corns and calluses can be long-term problems if you consistently wear shoes that do not fit properly. Even with good footwear, you may continue to have painful corns and calluses if there is some abnormality in your gait or foot structure that causes unusual stress on parts of your feet when you walk.

Preventing corns and calluses

In most cases, you can help to prevent corns and calluses by wearing shoes that fit properly. In particular, choose low-heeled, comfortable shoes that have enough space around the toes. Wear socks to cushion any areas of unusual rubbing or pressure, and use foot powder to reduce friction.

Treating corns and calluses

If your corns and calluses are painful, your doctor may shave away some of the thickened skin to relieve pain and pressure in the affected area. Although many people can do this themselves, podiatrists and other foot specialists can make sure the procedure is done safely. Your doctor also may recommend that you modify your footwear to prevent your problem from returning. For example, pads or "donuts" made of moleskin, lamb's wool, foam or felt will cushion the affected area. Corrective shoe inserts will redistribute the forces that cause friction and pressure inside your shoes, relieving some of the stress on your feet when you walk.

Your doctor may ask you to return regularly to have your feet examined and your corns and calluses shaved, if necessary.

You also can minimize corns and calluses by regularly rubbing them with a pumice stone, which is available in most drug stores.

After the corn or callus is shaved down, application of salicylic acid plasters or pads (available over-the-counter) can be helpful.  However, this treatment should not be used by people with nerve disease (neuropathy) or circulation problems in the feet.

In rare cases, foot surgery may be necessary to treat corns and calluses that keep returning and are not relieved by padding, shoe inserts and periodic shaving. Never try to shave or cut a corn or callus on your own. Instead, use a pumice stone to trim it down safely.

When to call a professional

Make an appointment to see your family doctor, orthopedic surgeon or podiatrist if you have painful corns or calluses.

If you have diabetes or poor circulation, examine your feet every day. For the best view, use a mirror to inspect the soles of your feet and the skin folds between your toes. If you see an area of redness, swelling, bleeding, blisters or any other problem, call your doctor promptly.


Although corns and calluses tend to return even if they are removed, this may be less likely if you use foot padding and shoe inserts.

Additional info

American Orthopaedic Foot and Ankle Society

American Podiatric Medical Association (APMA)

American College of Foot and Ankle Surgeons

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.