What is mmHg and What Compression Level is Right for You?

what is mmHg on VIM & VIGR Compression Socks

Compression socks work by gently compressing (we like to think of it more like a hug) your leg to move blood more efficiently through your leg. Compression is measured by mmHg (millimeters of mercury.) Our compression socks use graduated compression technology, this means that our socks are tightest in the ankle (highest mmHg) and gradually less tight towards the top of the sock. This guides blood up and through the leg, preventing varicose veins, swelling, and blood pooling. Compression socks can be worn running, at work, hiking, traveling, and are often prescribed to people with chronic illness by doctors. You may be wondering, how can some socks cover all of these hobbies? This is because compression socks can come in different pressure levels, fabrics, and sizing.  

Now you may be wondering, “which compression level is right for me?” In this article, we will take you through all of the various compression levels and activities they correlate to.  

We asked Caitlin Reid, a physiotherapist with a special interest in holistic and 

environmental well-being, to help us break down what each compression level means: 

If you’re sick of daily swelling and aching in your lower legs, it’s time to find a compression sock or stocking to help. The first step is deciding which level of compression you need. Whether you’re looking to use compression socks to help you recover after a hard workout, help a swollen injury  heal or help you manage a chronic illness, there is a level of compression to suit you.

What Is mmHg?

MmHg or millimeters of mercury is a measurement of pressure, originating from the pressure a 1 millimeter-high column of mercury could generate. Despite this, it’s not a common measurement outside the medical field. Within medicine though, mmHg is commonly used; both intracranial pressure (pressure inside the skull) and blood pressure are measured in mmHg. For science lovers out there, 1 mmHg is equivalent to 1/706th of an atmosphere of pressure.

Compression Socks and mmHg

Compression socks and stockings aren’t all the same. They are made according to different levels of compression. This compression comes in a range divided into different classes under two main classifications: Afnor (Association Française de Normalisation) and RAL (European Union classifications). Each classification utilizes ranges, as compression garments are crafted with graduating levels of compression. This means the compression is highest at the ankle (which is the higher number of the ranges below), and slowly decreases as it moves up your leg (terminating at the lower number in each range).

Below is an outline of how both systems break down the level of compression:


  • Class 1: 10-15 mmHg (Very light compression)
  • Class 2: 15-20 mmHg (Light compression)
  • Class 3: 20-36 mmHg (Moderate compression)
  • Class 4: 36+ mmHg (Strong compression)


  • Class 1: 18-21 mmHg (Light compression)
  • Class 2: 23-32 mmHg (Moderate compression)
  • Class 3: 34-46 mmHg (Strong compression)
  • Class 4: 49- mmHg (Very strong compression)

What Is the Best Compression Level for Sport Recovery?

To help muscles recover after sports, compressions socks and stocks are usually Afnor Class 2: 15-20 mmHg. Using compression at this level can boost the tissue repair of micro tears that occur during normal exercise. These micro tears cause swelling, leading to post-activity soreness.

Compression socks, leggings and sleeves work as a pump to stop this swelling from occurring. They enhance the transport and elimination of water and lymph fluid, as well as boost the circulation of metabolites. New research even shows compression can reduce the levels of inflammatory molecules and the enzyme creatine kinase.

Not only do compression stockings and socks help make your muscles feel less achy after exercise, but they also decrease muscle fatigue and may even minimize perceived exertion and increase agility.

What Is the Best Compression Level for People Who Sit All Day at Work?

Sitting all day at work can cause swelling and aching in your legs and feet. This swelling is known as occupational edema. The best way to minimize this swelling is by wearing compression socks or stockings. For these garments to be effective, though, they need to have the right level of compression.

To find the best compression level for people who work in different positions, one study looked at 58 people in three different groups with:

  • Sitting jobs
  • Standing jobs
  • Mixed

According to the study, of these people, no one had any illnesses that would cause increased swelling in their limbs. Each person had volumetric measurements of both limbs taken at the end of three consecutive days:

  • Day 1: No compression garment worn
  • Day 2: 15-20mmHg compression garment worn
  • Day 3: 20-30mmHg compression garment worn

After day two, significantly lower volumetric variations were observed in all three groups. Plus, the reduction of measured edema was more significant in individuals working in a prolonged seated position.

In other words, they concluded: 

  • Regardless of if you stand or sit at work (or both), you will experience less swelling in your legs and feet if you wear compression garments.
  • Particularly if you have a sedentary job, wearing compression garments of 15-20 mmHg dramatically helps minimize leg swelling and subsequent discomfort versus not wearing them.

    Who Are Medical Compression Stockings For?

    A number of chronic illnesses can increase the level of swelling you experience in your legs. These include:

    • Venous leg ulcers
    • Diabetes
    • Sleep apnea
    • Liver disease
    • Chronic venous insufficiency
    • (from smoking, taking the contraceptive pill, obesity, recent surgery and more)

    For this population, there are medical-grade compression socks and stockings available. Compression is generally considered medical grade if it’s 20 mmHg and above.

    Are Medical Compression Stockings for Everyday Life?

    Absolutely. Medical-grade compression isn’t only for those who suffer from a chronic illness or increased DVT risk. If wearing compression of 15–20 mmHg doesn’t seem to be minimizing the swelling in your legs enough, higher-grade (or medical-grade) compression may be more effective.

    It’s important to note, though, significant swelling in the legs is not normal for most people in everyday life. Let your doctor know about the swelling so they can see if there’s a more serious cause.  

    Where Can You Buy Fashionable Medical Compression Stockings?

    Thanks to innovative compression brands like VIM & VIGR, medical compression stockings don’t have to ruin your outfit, whether you’re flying overseas or sitting all day at work. Offering everything from brightly striped compression socks for under your suit at work to more subtle black compression stockings that are perfect for pairing with a dress and boots, great brands make caring for your leg health easier and more stylish than ever. Medical compression stockings aren’t just the white stockings you see in hospitals anymore; they can be a fashionable part of your regular, wearable wardrobe.

    Whether you’re looking to boost your tissue healing after a long run or you need a stylish way to minimize the swelling and discomfort in your legs at work, there is a level of compression sock or stocking perfect for you. Find a stylish compression brand and choose the mmHg that suits your needs.


    Caitlin Reid is a freelance journalist, copywriter and PR coordinator with over 10 years of experience

    with clients around the world. She is also a physiotherapist with a special interest in holistic and

    environmental well-being, blending the realms of evidence-based medicine with inspiring holistic health.



    On top of offering a variety of compression garments, we offer our compression socks in a variety of fabrics so you can figure out what is most comfortable for you day to day! Our compression socks come in cottonmerino woolnylon, and moisture wick nylon. 

    Our 4 functional fabrics are as follows: 


    Our 200 needle count cotton blend is soft and made with natural fibers. The flexibility in our cotton fabric allows for our most spunky designs, and many customers report that their feet stay cool while wearing them - even in the summer months!



    We use the highest quality (sustainably sourced) Merino Wool for our socks. This 200 needle count fabric is known for its moisture-wicking and temperature regulating ways. Customers love this fabric for everyday wear, and for outdoor activities!



    For the longest time, we have knit our nylon socks on a 400 needle count machine, this left a high quality sleek feel to the sock, and a 4 way stretch that was unmatched. However, it limited our ability to make fun designs, and left a seam in the toe. In 2022, we released another version of our nylon sock called Choice Nylon. This uses the same fabric as our Classic Nylon socks, but leaves a softer feel and allows for more designs. All while eliminating the toe seam as well. We will be keeping our Classic and Choice Nylon around for a while, so let us know which one you like better!



    This high-quality nylon is also great for temperature regulation. It uses a different fabric than our Classic Nylon and Choice Nylon socks and is knit on a 400 needle count machine. These socks give the feeling of stockings and are loved by many of our customers!  

    Finding your perfect compression sock will take some trial and error. Luckily, we have a 100% satisfaction guarantee and allow free returns if the sock you get isn’t perfect. When choosing a sock, we recommend looking at your lifestyle and health needs.












    • VIM & VIGR Customer Service

      Hi Greici and Kristi – for long hours of flight, we would highly recommend our 15-20 mmHg compression socks. They are ideal for all-day, every day wear, and offers moderate support to reduce ankle and leg swelling, ease tired and achy legs, and aid in muscle recovery. They are commonly used for travel, mild to moderate edema, pregnancy, spider and varicose veins.

    • Kristy Wood

      What level MMHG is recommended for a 14 hour international flight?
      Thank you!

    • Greici

      Hi there, I am 10 weeks pregnant and looking for a compression stockings for my flight 10h travel.
      I am not sure which one should I get.
      Thank you

    • sandra bennett

      Hello. I am traveling on a plane for at least 12-14 hrs. What mmhg would you recommend?
      I purchased 20-30mmhg already, and they are easy to put on and feel like they provide light compression.

    • Carol

      Do you have a light compression ankle sleeve. I have arthritic hands and have trouble getting the higher compression sleeves on and off.

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