A stye looks like a small, red, pimple-like bump at the edge of your eyelid. It forms right at the base of an eyelash or just under the eyelid margin, and it’s almost always tender or painful to the touch. Most styes develop a visible white or yellow head within a day or two, similar to a pimple that’s come to a point. The surrounding eyelid typically looks swollen and red.
External vs. Internal Styes
The classic stye that most people picture is an external one. It appears on the outer surface of your eyelid, right along the lash line. You can usually see the raised bump clearly, and it may develop a small pus-filled head that points outward. When it drains, the discharge comes from the outer eyelash area.
Internal styes form on the inner surface of the eyelid, inside the lid rather than along the lash line. These are harder to see without pulling the eyelid back. You’ll notice generalized swelling of the lid and feel a deep, aching tenderness, but the actual bump is hidden against the eye. If an internal stye drains, the pus releases on the inner conjunctival surface rather than the outside of the lid. In both types, swelling can sometimes spread across the entire eyelid, making one eye look noticeably puffier than the other.
What It Looks Like Day by Day
A stye doesn’t appear fully formed. In the first hours, you’ll likely notice a tender, slightly swollen spot on your eyelid that feels sore when you blink. The area turns red, and within a day the bump becomes more defined. Over the next day or two, many styes develop a visible pustule, a small yellowish or whitish point at the center, similar to a whitehead.
Most styes resolve on their own in one to two weeks. The bump gradually shrinks, the redness fades, and the tenderness disappears. Warm compresses held against the eyelid for 10 to 15 minutes several times a day can speed this along by encouraging the blocked gland to open and drain. You may notice some crusting along your lashes or a small amount of yellowish discharge as the stye clears, which is normal.
Stye vs. Chalazion
These two eyelid bumps are easy to confuse, but they look and feel quite different. A stye is red, sore, and sits right at the eyelid’s edge near the lash line. It hurts. A chalazion, by contrast, is a firm, round lump that usually develops farther back on the eyelid, away from the lash line. Chalazia are typically painless, at least at first. You might not even realize one is forming until it’s large enough to see or feel.
As a chalazion grows, it can cause some redness and mild tenderness, which is where the confusion with a stye comes in. The key difference is timing and pain: a stye is acutely painful from the start and looks inflamed, while a chalazion develops gradually and is more of a firm, rubbery bump without that angry red appearance. A stye that doesn’t resolve after several weeks sometimes turns into a chalazion as the acute infection fades but the blocked gland remains swollen.
Signs of a More Serious Problem
A straightforward stye stays localized. The redness and swelling are limited to the area around the bump itself. If redness and swelling begin spreading beyond the bump to involve the entire eyelid and the skin around the eye socket, that can signal a deeper infection called periorbital cellulitis. This is especially concerning in children. A fever combined with pain and swelling around the eye socket warrants immediate medical attention. Vision changes or a bulging eye are more urgent signs that infection has spread deeper into the tissues behind the eye.
A stye that keeps coming back in the same spot also deserves a closer look. A rare type of eyelid cancer can mimic the appearance of a recurring stye or chalazion. It may appear as a small, painless lump on the upper eyelid that looks pink, yellowish, or red-brown. The eyelid skin around it may thicken over time. Any eyelid bump that recurs in the same location, doesn’t heal after several weeks, or looks unusual compared to a typical stye should be examined by an eye doctor to rule out something more serious.
What Causes Them
Styes are caused by a bacterial infection in the tiny oil glands or hair follicles along your eyelid. Every eyelash has small glands at its root, and your eyelid contains dozens of oil-producing glands along its inner surface. When one of these glands gets clogged and bacteria multiply inside it, the result is a localized abscess: the red, tender bump you see. The infection is superficial and contained, which is why styes almost always resolve without antibiotics or medical intervention. They’re common and not a sign of poor hygiene, though touching your eyes with unwashed hands or sleeping in old eye makeup can increase the odds of developing one.