Anal warts are small, flesh-colored or grayish growths that appear on or around the anus. They can be as tiny as 1 to 2 millimeters (about the size of a pinhead) or, in rarer cases, grow to several inches across. Most start as soft, slightly raised bumps that are easy to overlook, especially when they first develop.
Shape, Color, and Texture
Anal warts don’t have a single “look.” Their appearance varies widely from person to person, and even from one wart to the next on the same body. They can be flat, dome-shaped, or pedunculated (hanging from a small stalk). The texture people most commonly associate with them is a rough, cauliflower-like surface, but many warts stay smooth and flat for their entire duration.
Color ranges from white to pink, red, purple, or brown, though the most common presentation is flesh-colored or slightly gray. They frequently appear in clusters rather than as isolated bumps. A single small papule can stay unchanged for months, or a cluster can gradually merge into a larger, irregular mass with a bumpy, brain-like surface texture.
Where They Appear
Warts can form on the skin surrounding the anus (perianal warts), inside the anal canal, or both. External warts are the ones you’re most likely to notice yourself, either by sight or by touch during bathing. They feel like small, soft, slightly rough bumps.
Internal warts are a different story. If they’re inside the rectum, you typically can’t see or feel them at all. The main clue that internal warts exist is often a mucous-like discharge from the anus, or occasionally a feeling of fullness or itching. Many people don’t realize they have internal warts until a clinician examines them.
How They Differ From Hemorrhoids and Skin Tags
The most common confusion is between anal warts and external hemorrhoids. Hemorrhoids tend to be swollen, dark red or purple, and more uniform in shape. They’re smooth and often painful or tender, especially during bowel movements. Anal warts, by contrast, are soft, irregularly shaped, and usually painless. They’re lighter in color and have a bumpy or textured surface rather than a smooth, swollen one.
Skin tags around the anus are also smooth, soft, and painless, which can make them tricky to distinguish from flat warts. The key difference is that skin tags are typically singular, consistent in color with surrounding skin, and don’t multiply or cluster. Warts tend to appear in groups and have a slightly rougher or more irregular surface, even when they’re flat.
What Causes Them
Anal warts are caused by human papillomavirus (HPV). About 90% of cases come from HPV types 6 and 11, which are considered low-risk strains, meaning they very rarely lead to cancer. The virus spreads through skin-to-skin contact, most commonly during sexual activity, though penetrative sex isn’t required for transmission.
One of the frustrating aspects of anal warts is the long gap between infection and visible symptoms. The incubation period averages around 3 months for women and 11 months for men, though it can vary significantly in either direction. This delay makes it difficult to pinpoint when or from whom you contracted the virus.
How They’re Detected
External warts are usually identified by visual inspection alone. If your doctor suspects internal warts, they’ll perform an anoscopy: a short procedure where a small, lubricated tube with a light is inserted about two inches into the anal canal. It takes only a few minutes and doesn’t require sedation, though numbing medication can be applied if you have pain.
For a more detailed look, a high-resolution anoscopy uses a diluted vinegar solution (acetic acid) applied inside the anal canal. Abnormal cells turn white in response to the solution, making small or flat warts that would otherwise be invisible much easier to spot under magnification. If anything looks suspicious, a tiny tissue sample can be taken during the same procedure to check under a microscope.
Growth Patterns Over Time
Anal warts are unpredictable. Some stay as tiny, barely noticeable papules for months or even years. Others multiply and merge relatively quickly into larger clusters. In people with weakened immune systems, growth tends to be faster and more extensive. There’s no reliable way to predict which pattern a given case will follow.
It’s also common for warts to recur after treatment. The virus can remain dormant in surrounding skin even after visible warts are removed. Recurrence rates are highest in the first few months after treatment, which is why follow-up exams are a standard part of management. Over time, most people’s immune systems suppress the virus enough that outbreaks become less frequent or stop entirely.