Compression Guide
Compression Guide
Which Compression Level Is Right For You?
Not all compression socks are the same. The level of pressure — measured in millimeters of mercury (mmHg) — determines what the sock can actually do for your legs. Getting the right level makes the difference between a sock that genuinely helps and one that just feels tight.
Here's everything you need to know to make the right choice — from a brand built by a vascular surgeon.
First — how does compression actually work?
True compression socks use graduated compression — meaning they are tightest at the ankle and gradually decrease in pressure as they move up the calf. This gradient is what makes them therapeutic.
By applying the most pressure at the ankle, the sock gently encourages blood to move upward toward the heart rather than pooling in the lower legs. This reduces swelling, relieves heaviness and fatigue, and over time supports healthier circulation.
A sock that applies uniform pressure throughout — or one that is simply tight — does not provide the same benefit. Graduated compression is a clinical design, not just a tight fit.
The three compression levels — explained simply
Most people fall clearly into one of these three categories. When in doubt, start lower and move up only if your symptoms require it — or book a free virtual fitting and we'll tell you exactly what you need.
The gentlest therapeutic level — and the best starting point for most people. Provides meaningful circulatory support without feeling restrictive. Ideal for daily wear, travel, and active use.
This level is right for you if:
- Your legs feel tired, heavy or achy by end of day
- You stand or sit for extended periods — nurses, teachers, office workers, retail
- You travel frequently and want to prevent swelling on flights or long drives
- You're pregnant or recently postpartum
- You exercise and want faster leg recovery
- You have mild varicose or spider veins with no significant symptoms
- You're new to compression and want to start gradually
No prescription required. Available over the counter and suitable for daily wear by most adults.
Shop 15–20 mmHg →The most clinically prescribed compression level in Canada. Provides firm, therapeutic support for people managing moderate venous conditions, significant swelling, or recovering from medical procedures. This is the level Dr. Jean Segal most commonly recommends to his clinic patients.
This level is right for you if:
- You have moderate to significant leg swelling (edema)
- You have varicose veins that cause discomfort or aching
- You have been diagnosed with chronic venous insufficiency (CVI)
- You are recovering from sclerotherapy or vein treatment
- You have a history of deep vein thrombosis (DVT) or blood clots
- You are post-surgical and your doctor has recommended compression
- Your physician or pharmacist has recommended medical-grade compression
No prescription required to purchase — but your physician's recommendation is helpful for insurance reimbursement. We provide insurance-ready receipts with every order. 20–30 mmHg is covered by the majority of Canadian extended health benefit plans.
Shop 20–30 mmHg →The highest therapeutic compression level available without a clinical fitting. Designed for people managing significant venous disease, lymphedema, or severe swelling. This level provides substantial pressure and should be used under medical guidance to ensure it is appropriate for your specific condition.
This level may be right for you if:
- You have severe chronic venous insufficiency
- You have lymphedema or significant lymphatic dysfunction
- You have active venous ulcers or a history of venous ulceration
- You have been specifically recommended 30–40 mmHg by your physician or specialist
- 20–30 mmHg has not provided sufficient relief for your symptoms
We recommend speaking with your physician before starting 30–40 mmHg compression — particularly if you have arterial disease, diabetes with vascular complications, or any condition that affects circulation in your lower extremities.
Shop 30–40 mmHg →
"The most common mistake I see is people choosing a compression level that's either too low to be effective, or too high without understanding whether it's appropriate for their circulation. When in doubt — start at 15–20 mmHg, wear it consistently, and reassess. If your symptoms persist or worsen, book a virtual fitting and see your physician. We'll help get it right."
— Dr. Jean Segal
General Surgeon with specialized training in vascular disease · Co-Founder, Dr. Johnny's
Not sure which level is right for you?
Take our 2-minute sock quiz and we'll recommend the right product for your situation. Or book a free virtual fitting with one of our compression specialists.
Take the quiz → Book a free fitting4 tips for getting the most out of your compression socks
The right level only works if you're wearing them correctly. Here's what our clinic recommends:
Put them on first thing in the morning
Before your legs have a chance to swell. Compression works best when applied before swelling starts, not after.
Make sure the fit is right
Snug but never painful. If the sock is leaving deep marks or cutting off circulation, it may be the wrong size — not the wrong level.
Wear them consistently
Daily wear gives the best results. Sporadic use — only on long days or flights — limits the cumulative circulatory benefit.
Replace every 3–4 months
Compression fibres lose elasticity over time. When your socks stop feeling as supportive, it's time for a new pair — not a higher level.
Canadian insurance coverage
20–30 mmHg and 30–40 mmHg compression socks are eligible for reimbursement under most Canadian extended health benefit plans — including plans offered through Sun Life, Manulife, Blue Cross, Great-West Life, and most employer group benefits.
When you purchase from Dr. Johnny's, we provide a detailed receipt that includes all the information your insurer needs to process your claim. Many of our customers recover the full cost of their socks through their annual benefit.
If your benefit year renews in January or spring, this is a great time to use your compression coverage before it resets. Learn more about insurance →
Frequently asked questions
Do I need a prescription to buy compression socks?
No — all three compression levels are available without a prescription. However, if you plan to claim 20–30 or 30–40 mmHg socks through your insurance, your insurer may ask for a physician's note or prescription depending on your plan. Check your benefits guide or contact your insurer before purchasing.
How do I know if the compression is too tight?
Compression socks should feel firmly supportive — not painful. If you experience numbness, tingling, skin discolouration, or significant discomfort, remove the sock immediately. This usually indicates the sock is the wrong size rather than the wrong level. Use our sizing guide or book a free virtual fitting before trying again.
Can I wear compression socks if I have diabetes?
It depends on the type of compression sock. Standard compression socks that apply graduated pressure can be worn by many people with diabetes — but only if circulation in the lower legs is not compromised. If you have peripheral arterial disease (PAD), neuropathy with reduced sensation, or significant circulation issues, compression may not be appropriate. We recommend speaking with your physician. Our non-binding diabetic socks are specifically designed for diabetic feet and do not apply compression — they are a safe daily-wear option for most people with diabetes.
What's the difference between compression socks and diabetic socks?
Compression socks apply graduated pressure to support circulation and reduce swelling. Diabetic socks are non-binding, seamless socks designed to protect sensitive diabetic feet from pressure points and friction — without applying therapeutic compression. They serve different purposes, and some people use both. Many of our customers with diabetes wear our diabetic socks daily and add compression when recommended by their physician.
How often should I replace my compression socks?
Every 3–4 months with daily wear, or when the socks no longer feel as supportive as they did when new. The therapeutic compression fibres lose elasticity over time, which reduces their effectiveness. Many Canadian insurance plans cover two to four pairs per year — so check your benefits before replacing at your own cost.
Can I wear compression socks during exercise?
Yes — compression socks are excellent for exercise, particularly running, cycling, and other activities that place sustained demand on the lower legs. They help reduce muscle vibration, support venous return during activity, and may speed up recovery afterward. Many athletes wear them both during and after training.
Ready to find the right sock for you?
Browse our full compression collection, take the quiz, or book a free virtual fitting — we'll make sure you get it right the first time.
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