Measuring for thigh high compression stockings requires three circumference measurements (ankle, calf, and upper thigh) plus one length measurement from your heel to the top of your thigh. Getting these numbers right matters because compression stockings that are too small will be painful and difficult to put on, while ones that are too large won’t deliver enough pressure to support circulation.
When to Take Your Measurements
Take your measurements first thing in the morning, before you’ve been on your feet. Prolonged sitting or standing slows circulation and can cause your legs and ankles to swell throughout the day. That swelling can add enough volume to push you into the wrong size. Measuring right after getting out of bed captures your leg at its baseline, which is what manufacturers use to design their sizing charts.
If you already deal with noticeable leg swelling or lymphedema, timing becomes even more important. Morning measurements reflect the size your leg returns to after a night of rest with your legs elevated. For significant or uneven swelling, a trained fitter at a medical supply store can help ensure the measurements account for your specific situation.
What You Need
All you need is a soft fabric measuring tape (the kind used for sewing, not a metal one) and a pen or marker to make small reference marks on your skin. Measure on bare legs, not over clothing. Stand with your feet flat on the floor and your weight distributed evenly on both legs.
The Four Measurements, Step by Step
Ankle Circumference
Find the narrowest part of your ankle, just above the ankle bone. Make a small mark there with a pen. Wrap the measuring tape around this point snugly but without compressing the skin. The tape should sit flat against your leg without gaps or twists. Record the number in inches or centimeters, depending on what your stocking brand’s sizing chart uses.
Calf Circumference
Move the tape up to the widest part of your calf. For most people, this is roughly halfway between the ankle and the back of the knee. You can find it by sliding the tape up and down slightly until you get the largest reading. Again, keep the tape level all the way around and snug without digging in.
Upper Thigh Circumference
This is the measurement that distinguishes thigh highs from knee highs. Measure the circumference of your upper thigh right at the gluteal fold, which is the crease where the bottom of your buttock meets the back of your thigh. This is typically the widest point of your upper leg and the spot where the stocking’s top band will sit. Keep the tape horizontal as you wrap it around, since angling it even slightly can throw off the number by an inch or more.
Leg Length
With your feet still flat on the floor, measure from the bottom of your heel straight up to the gluteal fold. This tells you how long the stocking needs to be to reach from your foot to the top of your thigh. Some brands also distinguish between “short” and “long” versions based on calf length. A calf length under 15.5 inches (measured from the floor to the back of the knee) typically falls into the short category, while anything over 15.5 inches calls for a long version.
Reading the Sizing Chart
Once you have your four numbers, compare them to the sizing chart for the specific brand and style you’re buying. This step is important because sizing is not standardized across manufacturers. A “medium” in one brand can cover a different range than a “medium” in another.
For example, one popular Sigvaris thigh high line lists a small as fitting thigh circumferences from 18 to 26 inches, a medium from 19 to 28.5 inches, and a large from 20.5 to 33 inches. Notice the overlap: a 20-inch thigh could technically fit into small, medium, or large depending on where your other measurements land. That’s why you need all four measurements, not just one. Your ankle and calf numbers help narrow down the right size when your thigh measurement falls in an overlapping zone.
Some lighter compression styles use simplified charts based on body weight instead of detailed circumferences. One Sigvaris sheer line, for instance, sizes its thigh highs as size A (up to 135 lbs), size B (135 to 180 lbs), and size C (180 to 230 lbs). These are convenient but less precise. If you’re wearing medical-grade compression (20 mmHg or higher), sizing by actual measurements gives you a better fit.
Common Mistakes That Affect Fit
The most frequent error is measuring at the wrong time of day. An afternoon measurement taken after hours of standing can easily be a full size larger than a morning one, especially at the ankle and calf. The second most common mistake is pulling the tape too tight or leaving it too loose. You want the tape to make full contact with your skin without creating any indentation. Think of it as resting on the surface, not squeezing.
Measuring over clothing, even thin leggings, can add enough bulk to skew your numbers. And measuring while sitting changes the shape of your calf and thigh enough to produce inaccurate readings. Stand up, distribute your weight evenly, and keep your leg relaxed rather than flexing.
If your two legs are noticeably different sizes, measure both. Some people need a different size for each leg, and most compression stockings are sold individually or in pairs of the same size. Knowing both sets of numbers lets you order accordingly.
What to Do if You’re Between Sizes
If your measurements place you right on the boundary between two sizes, the general rule is to size down for a snugger fit that delivers more compression, or size up if comfort is your priority and you’re wearing a lower compression level. For medical-grade stockings prescribed for a specific condition, a trained fitter can help you decide which direction to go based on your needs. Many medical supply stores and hospital pharmacies offer fitting services at no extra charge.
Keep your written measurements handy when you order. Sizing charts change between product lines even within the same brand, so you’ll want to re-check every time you try a new style rather than assuming your old size carries over.