A stye looks like a small, painful red bump on the edge of your eyelid, similar in appearance to a pimple. It typically forms right at the base of an eyelash and often develops a visible yellow or white pus point at its center within a day or two. The surrounding skin becomes swollen, red, and tender to the touch.
External Stye Appearance
The most common type of stye, called an external hordeolum, forms along the outer edge of your eyelid where your eyelashes grow. It starts as a localized area of redness and tenderness around a single eyelash. Within one to two days, the bump becomes more defined. A small yellowish pustule develops at the base of the affected eyelash, surrounded by redness and firm swelling.
What makes an external stye easy to spot is its location. It sits right on the lash line, and you can usually see which eyelash is involved. The bump itself is typically small, maybe the size of a pea or smaller. While the area immediately around the infected lash is swollen and inflamed, the rest of the eyelid usually looks normal in the early stages. As the infection develops, though, swelling can spread across more of the lid.
Internal Stye Appearance
An internal stye forms on the inner surface of the eyelid rather than along the lash line. You won’t see it as easily from the outside. Instead, the eyelid itself looks red, swollen, and puffy without an obvious bump on the skin’s surface. If you gently flip the eyelid (or a doctor does), there’s a small raised area or yellow spot visible on the inner lining.
Internal styes tend to cause more generalized eyelid swelling because the infection sits deeper in the tissue. They can be harder to identify on your own since the main visible sign from the outside is just a swollen, tender eyelid without a clear pimple-like head.
How a Stye Changes Over Time
A stye doesn’t appear fully formed. In its earliest stage, you might notice a slight tenderness or irritation near one eyelash before any visible bump appears. The area then becomes red and begins to swell, and within a day or two the characteristic pus-filled head develops. The bump looks most like a pimple at this point, with a yellow or whitish center surrounded by inflamed skin.
Most styes resolve on their own within one to two weeks. As it heals, the bump gradually shrinks, the redness fades, and any pus drains naturally. You might notice some crusting around the eyelash as this happens. Warm compresses can speed the process by encouraging drainage. If pus or blood actively leaks from the bump, or if the stye hasn’t started improving after 48 hours of home care, that’s worth getting checked.
How to Tell a Stye From a Chalazion
Styes and chalazia are the two most common eyelid bumps, and they look different in a few key ways. A stye is painful from the start, sits right at the eyelid’s edge near the lash line, and has visible redness and a pus point. A chalazion is a firm, round bump that develops farther back on the eyelid, away from the lashes. It’s usually painless, at least initially, and grows more slowly.
A chalazion forms when an oil gland deeper in the eyelid gets blocked without a bacterial infection. It can eventually become red and swollen if it gets large enough, but the early stages are noticeably different: you’ll feel a firm lump under the skin with little to no pain. Styes, by contrast, hurt from day one and look inflamed immediately. The bacteria involved in styes is almost always Staphylococcus aureus, the same germ behind common staph infections, which explains why the bump looks and behaves like an infected pimple.
Why Styes Form
Each of your eyelashes has one or two tiny oil glands at its root. These glands produce oils that help keep the eyelid lubricated. When debris, dead skin, or dried oil blocks the duct of one of these glands, bacteria that normally live on your skin can get trapped inside and multiply. The result is a small abscess: the red, swollen, pus-filled bump you see as a stye.
Styes are more common in adults than children, likely because adults produce thicker oils in their eyelid glands and are more prone to chronic eyelid inflammation. People with conditions like rosacea or blepharitis (ongoing eyelid irritation) get them more frequently. Touching your eyes with unwashed hands, sleeping in eye makeup, or using old cosmetics can also introduce bacteria to the lash line. Styes are extremely common in everyday medical practice, though exact numbers on how many people get them each year haven’t been tracked.
Warning Signs of a Spreading Infection
A typical stye stays small and localized. What you’re watching for is redness or swelling that moves beyond the bump itself. If the redness and swelling spread across your entire eyelid, or extend into your cheek or other parts of your face, that suggests the infection is no longer contained and needs medical attention. Vision changes, fever, or a stye that keeps growing after several days are also signals that something more serious may be going on, such as a deeper skin infection called periorbital cellulitis.