Measure the length of your child's foot by standing them on a flat surface with your full weight on your foot, then measure the distance from the back of your heel to the tip of your longest toe (normally their big toe).This measurement will give you their foot length. This will allow for between 6mm - 12mm of growing room (the maximum recommended is 15mm). You do not have to add the growing room onto the foot length. If your child is right on the maxiumum recommended you may want to go up a size.
As you can see the Xplorer, Step Up and I-Walk ranges include size 22. This is because of the different developmental stages children can be at when wearing this size - some are walking confidently, others are still finding their feet!
For more information on how to measure and a downloadable foot measure visit our Sizing Information page