Z-CoiL Footwear generally runs true to size.  Order the size that you normally wear. If your current shoes are a variety of sizes, use the chart below to determine what size you are in a Z-CoiL. If you are familiar with EURO or CM size please see the conversion to Australian/United States standard sizing below.  If you would like to check your size — step on a ruler or measuring tape and use the guide below. Measure from the longest toe to the back of the heel. Sometimes it is easier to get someone to trace around your foot on a piece of paper and then measure the drawing. 



All Z-CoiL footwear is designed with an E width. All Z-CoiLs are built with a rounded heel and raised arch for a great ergonomic fit. We strive to support each contour on your feet. The toe box of Z-CoiL is wider than normal shoes and designed to prevent irritation in the toes and ball of the foot.  It's important that you wear shoes that prevent cramping or squeezing of the toes. Tension on the toes can easily lead to bunions and disfigurement of the toes and ball of the feet. Its important to sets your toes free and allow them to spread out naturally with each step.

There is a subtle difference in fit between some styles. Our narrowest fitting shoe style is the Sofia. Our widest fitting shoe style is The Legend with Velcro straps. 


Z-CoiL does not make half sizes. Instead all Z-CoiL Footwear ship with an extra 3 mm insert that makes up 1/2 size. 


If you require a half size, please order the next size up and add the insert as follows:
1. Remove the black Z-CoiL Insole
2. Insert the 1/2 Size foam Insert
3. Replace the original black Z-CoiL Insole on top of the foam insert.


Z-CoiL has 4 different sized springs. The size of the shoe dictates what size of spring is loaded at the factory. In some cases, customers will choose a softer or stiffer spring based on their weight or gait type. Your objective should be to compress the spring about 75% during a normal walk (or a normal run — if you run in Z-CoiL’s). If you “bottom out” on the spring, you may want to consider a stronger spring. If you feel your shoe is too stiff, you may consider a softer coil. The vast majority of consumers do not change the factory spring strength.

  • Women’s sizes 5-7 are factory loaded with a small spring.
  • Women’s sizes 8-11 and Men's 8-9 are factory loaded with a medium spring.
  • Men’s 10-13 are factory loaded with a large spring.
  • Men’s 14+ are loaded with an XL spring.
Coil Diameter  ​Coil Size      ​Typical Weight   

​Weight range of successfully fitted customers

​6.2 mm ​Small ​up to 68 kgs    ​40 to 136 kgs
​6.5 mm ​Medium ​54 - 90 kgs ​40 to 159 kgs
​7.2 mm ​Large ​72 -108 kgs ​40 to 159 kgs+
​7.5 mm ​X-Large ​100 kgs+ ​40 to 159 kgs+


If you think you will need a different spring strength than the factory loaded one, just write a note at checkout describing your situation with your order.​​​​​​​​


Very flat or very high arches

If you have very flat or very high arches and don't already have a custom orthotic, consider the addition of our Z-Fit Custom Arch Insoles to wear inside your Z-CoiLs.

You want to achieve the entire bottom surface of your feet to be in contact with the shoe.