How to Measure the foot
Measure the length of your child's foot while they're standing upright. Be sure to measure both feet, as their left and right foot may be different lengths. Start by standing your child up against a wall with their weight evenly distributed between both feet. Place their heel against the wall and a book on the floor so that it is touching their longest toe. Then measure both feet in centimeters from the heel on the wall to the longest toe against the book. You can check our 'inside measurements' on every shoe to see which size correspondes to the cm's of your childs foot.
When buying rain boots for your child, avoid buying ones with too much room for growth as rain boots cannot be strapped to the foot in the same way other footwear can. If the rain boots are far too big, the feet and heels will slide back and forth. This could mean they wear down faster, both on the inside and the outside.
Rain boots are already fairly large and wide compared to other shoes and boots. You should therefore make sure to choose a pair with an appropriate volume, both in terms of shaft and width. If you want a little extra warmth and a more snug fit, you can add an extra wool sole inside the boots. A thick pair of stockings or wool socks can also help.