Size Guide

We offer a free size exchange on sizes for un-worn Crazy Arms.

How to choose the right size

Upper-Arm Width (Bicep)
Measure around the bicep with arm straight.
Check against the ranges below.

Measure from wrist bone to arm pit.


Crazy Arms are designed to fit like a second skin for athletic activity. They need to be tight enough so they do not fall down during activity (swinging a golf club, bowling a ball, winching a sail), but comfortable to wear.

Adult Small
For smaller adults or early teens, designed for a bicep measurement 24-27cm.

Adult Regular 
Fits 70% of the population, for biceps 28-32cm.

Adult Relaxed
For those with larger biceps 33 -36cm.

Adult XL 
For those with larger biceps over 36cm.

Regular or Relaxed Fit?

Crazy Arms are designed to fit like a second skin for athletic activity.

This should feel a little tight on first wearing, but will ease to a snug fit after one or two wears.

If you are using Crazy Arms for activities with high arm movement (e.g. golf, tennis, cricket, sailing), we recommend the "Regular" Fit up to a 32cm bicep.

This will help ensure the upper elastic band keeps the sleeve in place.


Age guide for kids is a guide only – kids do grow at very different rates!

Kids X-Small
Kids under 115cm high (45”) Ages 2-4.

Kids Small
Kids between 115-135cm high (45-53") Ages 5-6.

Kids Medium
Kids between 135-150cm high (53-59") Ages 7 -10.

Adult Small
Kids between 150-160cm high (59-63”) Ages 11 and over of regular frame.

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