What Is Compression Wear? | Pressure That Works

Compression wear is tight-fitting clothing that applies graduated pressure to improve blood flow, reduce swelling, and support tired legs.

Compression wear looks like ordinary athletic gear or stockings, but the fabric does real work. The graduated pressure—firmest at the ankle, easing as it moves up—helps push blood back toward the heart and keeps fluid from pooling in your lower legs. People reach for it after surgery, during long flights, on their feet all day, or when swelling becomes a recurring problem. The fit determines whether it helps or hurts, so knowing how compression works and how to size it matters before you buy.

How Compression Wear Works

Compression garments press on your legs to improve blood flow, per standard medical guidance. The pressure is highest at the farthest point from your heart and gradually decreases moving upward. That gradient helps your veins push blood upward against gravity and reduces the swelling that comes from fluid building up in tissues.

People use compression wear for a handful of reasons:

• Swelling or edema reduction in the legs and feet
• Relief from aching, heavy legs or varicose vein symptoms
• Support during long periods of sitting, standing, or travel
• Recovery support after surgery or injury, when a clinician recommends it

Compression Levels: What The Numbers Mean

Compression strength is measured in millimeters of mercury (mmHg), and that number is printed on the label. The most common levels are 15–20 mmHg, 20–30 mmHg, and 30–40 mmHg. Higher numbers mean firmer pressure.

Most people start with 20–30 mmHg, which offers meaningful support without being overwhelming. If that feels too firm, dropping to 15–20 mmHg often works better; if more support is needed, 30–40 mmHg is the next step up. Medical-grade compression above 20 mmHg typically requires a prescription or clinician fitting, and anyone with peripheral artery disease, diabetes-related nerve damage, or skin infections should talk to a doctor before using compression at all.

A well-fitted garment should feel snug but not painful. It should stay in place without rolling or bunching, and the pressure should feel consistent with no gaps. Most compression wear is made for daytime hours and should be removed before bed unless it’s specifically designed for sleep or a clinician says otherwise.

Getting The Size Right

The single most common mistake is guessing the size. Compression garments need exact measurements, and those measurements should be taken when your legs are least swollen—usually first thing in the morning. Use a soft tape measure on bare legs with your feet flat on the floor.

For knee-high stockings, measure just above the ankle bone, then below the knee, and record the ankle-to-knee length. Take circumference measurements at several points: 5 cm, 15 cm, 25 cm, and 30 cm above the ankle. Because every brand sizes differently, follow the specific brand’s chart with your numbers rather than assuming a small, medium, or large fits.

Proper positioning matters too. For knee-highs, the heel should align with your actual heel and the top should sit two finger widths below the knee bend. Thigh-high tops sit two finger widths below the gluteal fold. Sleeves should reach the wrist crease at the bottom with the top band two finger widths below the armpit crease.

When the fit is right, you may notice athletes and active folks wearing compression for performance and recovery. If you’re curious about options built for the court, our tested roundup of compression gear for basketball covers sleeves and tights that hold up under hard play.

How Long It Lasts And How To Care For It

Compression garments don’t last forever. With regular use, most lose their effectiveness after 3–6 months and should be replaced if they’re older than six months, visibly worn, stretched out, or no longer providing the same support. The elastic fibers degrade with washing and wear, which is why care matters.

Hand washing is the safest method: use tap water and mild detergent, skip the bleach, fragrance, dyes, and fabric softener, and rinse thoroughly. Roll the garment in a towel to remove excess water, then lay it flat to air dry away from direct sunlight. Never wring it out. If machine washing, use a delicate cycle in cold water at or below 40°C (104°F) and place the garment in a lingerie bag. Air dry when possible; if you must use a dryer, use the lowest heat or delicate cycle.

Watch for warning signs while wearing compression. If you feel persistent pain, skin irritation, skin breakdown, or worsening swelling, remove the garment and contact a healthcare provider. Avoid lotions underneath compression wear, skip dry cleaning, and consider donning gloves to put the garments on—they reduce strain on the fabric and make the process easier.