What to know before you buy compression socks

What the mmHg number means

The pressure of compression socks is given in millimeters of mercury, mmHg. Cleveland Clinic groups the levels as mild at 8 to 15 mmHg, moderate at 15 to 20, firm at 20 to 30 and extra-firm at 30 to 40, and describes extra-firm as medical-grade compression used under a doctor's supervision.

Our Knee-High Compression Socks are listed at 15 to 20 mmHg, which is the moderate band sold over the counter. Our cushioned knee-highs and compression crew socks do not list an mmHg figure, so treat them as snug athletic socks rather than graded compression.

When to ask a doctor first

Cleveland Clinic advises against compression socks over open wounds, skin infections or very fragile skin, and recommends talking to a provider first if you have severe swelling, peripheral artery disease or reduced feeling in your legs from neuropathy or diabetes.

If you are buying compression socks for a condition, your doctor can tell you which level you need and whether an over-the-counter pair is enough.

Getting the fit right

A sock that is too tight or bunched can do more harm than good. Cleveland Clinic lists skin irritation and discomfort as the common side effects and says a proper fit without wrinkles on dry skin helps avoid them. Our knee-high socks come in S/M and L/XL, so pick the size by your calf and check it on the product page.

Take the socks off if you feel pain, numbness or tingling, and do not sleep in them.

Our compression socks

• Plush Footbed Crew Socks, shoe size 5 to 8
• Knee-High Compression Socks, S/M, L/XL
• Cushioned Knee-High Compression Socks, S/M, L/XL
• Arch Band Gym Crew Socks, shoe size 7 to 13
• Terry Sole Crew Socks, shoe size 8 to 13
• Athletic Compression Crew Socks, shoe size 8 to 13