Compression Garment Pressure Calculator

Calculate the actual pressure delivered by compression garments using Laplace's Law. Essential for medical compression stockings, sleeves, and post-surgical garments.

Select the body part for compression garment

Measure around the widest part of the body part

Medical compression garment classification

Only used if Custom selected above

How many layers of compression material

How tight the unstretched garment is compared to your body

P = (T × n) / R, where P = pressure (mmHg), T = garment tension, n = number of layers, R = body part radius (circumference / 2π). Pressure increases with more layers and tighter fit, decreases with larger body part radius.
For a calf with 40cm circumference (radius ~6.4cm), Class 2 garment (27.5 mmHg), 1 layer, tight fit (20% smaller): Effective pressure ≈ 28-32 mmHg with typical variation.

What is Laplace's Law for compression garments?

Laplace's Law states that pressure (P) = (Tension × Number of layers) / Radius. For cylindrical body parts, this means pressure is inversely proportional to the radius - smaller circumferences receive higher pressure from the same garment. This is why compression garments are sized precisely for each body part.

What compression class do I need?

Class 1 (18-21 mmHg) is for mild edema, tired legs, and prevention during travel. Class 2 (23-32 mmHg) is for moderate varicose veins, post-sclerotherapy, and mild lymphedema. Class 3 (34-46 mmHg) is for severe venous disease and moderate lymphedema. Class 4 (>50 mmHg) is for severe lymphedema and requires professional fitting.

How do I measure for compression garments?

Measure circumference at the widest point of the body part while standing. For legs, measure ankle (narrowest), calf (widest), and thigh. Measure in centimeters for best accuracy. Take measurements in the morning before swelling increases. Use a flexible tape measure and keep it snug but not tight.

Why does the same garment feel tighter on smaller body parts?

According to Laplace's Law, pressure = tension / radius. A garment with the same tension will exert 2× the pressure on a body part with half the radius. This is why compression garments must be precisely sized - a "one size fits all" approach can lead to dangerous pressure on smaller limbs while being ineffective on larger ones.