Varicose veins are swollen, twisted blood vessels that bulge just beneath the skin’s surface, typically appearing blue or purple. They have a rope-like, gnarled look and are wider than 3 millimeters in diameter. Most people notice them on the legs, ankles, or feet, where they can range from mildly visible to dramatically raised and winding.
The Classic Appearance
The most recognizable feature of a varicose vein is its shape: twisted, cord-like, and visibly raised above the surrounding skin. Unlike the flat, faint lines of normal veins, varicose veins look like thick, knotted ropes pushing outward. Their color is typically blue or dark purple, though this can vary depending on your skin tone. On lighter skin, they tend to stand out sharply. On darker skin, you may feel them as raised ridges before you see color changes.
They appear most often along the inner calf, the back of the leg, and around the ankles and feet. Some people develop just one or two visible veins, while others have clusters that spread across a large section of the leg. The veins don’t follow a straight path. Instead, they twist and turn in irregular patterns beneath the skin.
Varicose Veins vs. Spider Veins
Spider veins and varicose veins are easy to confuse, but they look quite different up close. Spider veins are less than 1 millimeter wide, appearing as thin red, blue, or purple lines that fan out in a web-like pattern. They sit flat against the skin and don’t bulge. Varicose veins are more than 3 millimeters wide, visibly raised, and have that distinctive ropy, twisted texture. Between the two, reticular veins (sometimes called “feeder veins”) fall in the 1 to 3 millimeter range and appear as flat, bluish-green lines without significant bulging.
Spider veins are primarily a cosmetic concern. Varicose veins can be cosmetic too, but they’re more likely to cause symptoms like aching, heaviness, or swelling, and they can progress to more serious skin changes over time.
Skin Changes Around Varicose Veins
When varicose veins have been present for years, the skin around them can start to change. This happens because the poor blood flow that caused the veins also damages the surrounding tissue. Early signs include discoloration, often a yellowish-brown or reddish staining around the ankles and lower legs. The skin may become dry, itchy, scaly, or thickened in patches.
In more advanced cases, the lower leg skin can become tight and leathery, a condition called lipodermatosclerosis. The area feels hard and woody to the touch, and the leg may look narrower just above the ankle while swollen below the knee, creating an inverted bottle shape. You might also notice small, ivory-white patches of scarring surrounded by darker pigmented skin and tiny visible capillaries. These white patches, called atrophie blanche, are star-shaped or irregular depressed areas that develop after small wounds heal poorly. They’re more common in middle-aged women with longstanding vein problems.
What a Clotted Varicose Vein Looks Like
Sometimes a varicose vein develops a blood clot near the skin’s surface, a condition called superficial thrombophlebitis. When this happens, the vein changes noticeably. Instead of its usual soft, squishy feel, it becomes a hard, red cord that you can feel just under the skin. The area around it turns red and swollen, and it’s warm and tender to the touch. This is different from the typical blue or purple color of an uncomplicated varicose vein. The redness and firmness are the key visual clues that something has changed.
When Varicose Veins Lead to Open Sores
The most visible complication of long-term varicose veins is a venous ulcer, an open wound that develops when blood pools in the lower leg for so long that the skin breaks down. These ulcers have a distinctive look: they’re shallow with irregular edges and well-defined borders. The base of the wound is usually moist and may have a yellowish coating of fibrin over a reddish, granulating surface.
Venous ulcers almost always appear in one specific spot: the inner ankle, over the bony bump called the medial malleolus. This region, sometimes called the “gaiter area” (the zone a short boot would cover), is where venous pressure is highest when you’re standing. If you see a slow-healing wound in this location combined with the skin changes described above, the underlying cause is very likely varicose veins or chronic venous insufficiency.
How Varicose Veins Progress Over Time
Varicose veins don’t always stay the same. Doctors classify chronic venous disease on a scale from C0 to C6, and knowing where you fall can help you understand what you’re seeing on your legs. At C0, there are no visible signs. C1 means you have spider veins or small reticular veins. C2 is the stage where classic varicose veins appear, with visible bulging and twisting.
From there, C3 adds noticeable swelling in the legs. C4 is when the skin changes begin: pigmentation, eczema, thickening, or those ivory-white scars. C5 means a venous ulcer has formed and healed, leaving a scar. C6 means an active, open ulcer is present. Not everyone progresses through all stages, and many people stay at C2 for decades without advancing. But recognizing the early skin changes at C4 is important because compression stockings and treatment at that stage can prevent ulcers from developing.
Globally, varicose veins affect roughly 10 to 30 percent of adults, with higher rates in women and in people whose jobs involve long periods of standing or sitting. They’re common enough that most people will recognize the look, but the later stages involving skin damage and ulcers are far less familiar and often go unrecognized until they’re well established.