A corn is a small, concentrated area of thickened skin on your foot, formed in response to repeated pressure or friction. What sets it apart from a regular callus is its defining feature: a hard, cone-shaped core of keratin that presses into the deeper layers of skin, often causing sharp or aching pain. Corns are one of the most common foot complaints, and while they’re rarely dangerous, they can make walking genuinely uncomfortable.
How Corns Form
Your skin is built to protect itself. When a specific spot on your foot experiences repeated rubbing or pressure, the outermost layer of skin responds by producing extra cells faster than normal. This process, called hyperkeratosis, creates a thick, protective buildup of tough skin. In a callus, that buildup is spread across a broader area. In a corn, the pressure is more focused, so the thickened skin compresses into a tight, cone-shaped plug that points inward toward the bone.
That central core is what makes corns painful. It acts like a small wedge pressing on the sensitive tissue underneath, and it can irritate nerve endings with every step. The harder the core becomes, the more it hurts.
Types of Foot Corns
Not all corns look or feel the same. There are three main types:
- Hard corns are the most common. They appear on the tops or sides of toes, especially over the joints where skin presses against shoes. They feel like a firm, raised bump surrounded by dry, flaky skin.
- Soft corns form between the toes, where moisture from sweat keeps them from hardening. They have a whitish, rubbery texture and can be surprisingly painful. Because the skin stays damp, soft corns are more prone to breaking down and becoming infected.
- Seed corns are tiny and tend to show up on the bottom of the foot in areas that don’t bear much weight. They’re usually painless and are the least troublesome of the three.
What Causes Them
The single most common cause is shoes that don’t fit properly. A toe box that’s too narrow squeezes the toes together and against the sides of the shoe. Heels that are too high shift your body weight forward onto the ball of the foot. Shoes that are too loose let the foot slide and rub with every step.
But footwear isn’t the only factor. Structural issues with the foot itself play a major role. Hammertoes force the middle joint of a toe upward, creating a pressure point that rubs against the top of the shoe. Bunions push the big toe inward, crowding the smaller toes. Bone spurs and arthritis can change foot alignment enough to concentrate pressure in new spots. Even the natural loss of fatty padding on the bottom of the foot, which happens with age, can allow bones to press more directly against the skin.
Walking barefoot, skipping socks, or spending long hours on your feet for work or sports can also contribute. Anything that creates a repetitive friction point is a potential trigger.
Corn vs. Callus vs. Wart
People often confuse corns with calluses or plantar warts, but each one looks and feels different. A callus is a broader, flatter area of thickened skin without a central core. It usually forms on the ball of the foot or the heel and is more of a general toughening of the skin than a focused pressure point. Calluses are often painless.
Plantar warts can look similar to corns because they’re small, flesh-colored, and rough. The key difference is texture: warts appear grainy and typically have tiny black dots scattered through them (these are small, clotted blood vessels). Corns look like a raised, hard bump with dry skin around them but no dark speckling. Warts are caused by a virus and can spread, while corns are purely a mechanical response to pressure.
Treating Corns at Home
Since the underlying cause is pressure, the most effective first step is removing whatever is creating that pressure. Switching to shoes with a roomier toe box, using cushioning pads, or wearing toe sleeves can reduce friction enough for the corn to gradually resolve on its own.
Soaking your foot in warm water for 10 to 15 minutes softens the thickened skin. After soaking, you can gently file the corn with a pumice stone, working in one direction to thin the hardened layers. The goal is gradual reduction over several sessions, not aggressive removal in one sitting.
Over-the-counter medicated pads and plasters contain salicylic acid, which works by dissolving the built-up keratin layer by layer. You apply the plaster directly over the corn and replace it every 48 hours, continuing for up to 14 days or until the corn lifts away. These products are effective for many people, but they require patience and careful placement. If the acid contacts healthy skin around the corn, it can cause irritation or chemical burns.
When Professional Removal Helps
If a corn is deep, keeps coming back, or doesn’t respond to home treatment, a podiatrist can remove it in the office through a procedure called enucleation. Using a small blade, they carefully pare away the thickened skin and extract the central core. The procedure doesn’t require stitches and provides immediate pressure relief. For corns driven by structural problems like hammertoes or bunions, a podiatrist may also recommend custom orthotics to redistribute pressure across the foot and prevent recurrence.
Preventing Corns From Coming Back
Corn removal treats the symptom, not the cause. Without addressing the friction source, corns almost always return in the same spot. Prevention comes down to a few practical habits:
- Shoe fit matters most. Your toes should be able to wiggle freely. There should be about a thumb’s width of space between your longest toe and the front of the shoe.
- Wear socks. Socks reduce direct friction between skin and shoe material. Make sure they fit smoothly without bunching.
- Use protective padding. Moleskin patches can cushion pressure points. Silicone toe caps or sleeves wrap around individual toes to protect the sides and tips from rubbing against each other or against the shoe.
- Address structural issues. If you have hammertoes, bunions, or an uneven gait, orthotics or corrective footwear can change how forces distribute across your foot.
Risks for People With Diabetes
Corns carry extra risk if you have diabetes or poor circulation. Nerve damage in the feet can make it hard to feel how much pressure you’re applying during self-treatment, and reduced blood flow slows healing. The CDC specifically advises people with diabetes not to remove corns themselves and not to use over-the-counter salicylic acid products, which can burn the skin without the person realizing it. Even a small skin break can become a serious infection when circulation is compromised. A podiatrist should handle any corn removal.
Signs of Infection
Most corns are nothing more than a nuisance, but an untreated or improperly treated corn can occasionally become infected, particularly soft corns between the toes where moisture lingers. Warning signs include redness spreading beyond the corn, warmth to the touch, swelling, pus, or increasing pain that doesn’t improve with rest. A skin infection that isn’t treated can progress to cellulitis, a deeper bacterial infection marked by fever, chills, and rapidly expanding redness. Cellulitis requires prompt medical treatment to prevent complications affecting the bone or bloodstream.