Buying shoes online is easy once you have one reliable number: your child's foot length. The good news is that how to measure child foot size is not complicated. You need about ten minutes, a calm moment, and three things you already own. This guide walks through it step by step, from toddlers who will not stay still to older children who are happy to help.
If your child wears a brace or orthotic, or you have been given specific advice by a clinician about fit, follow that advice first. This guide is general information, not medical advice.
What you need (paper, pen, ruler)
- A sheet of paper that is larger than your child's foot (A4 works for most children)
- A pen or a sharp pencil
- A ruler or tape measure with centimetres
- A flat, hard floor and a wall to push the paper against
- The socks your child will wear with the shoes, if you are measuring for a particular pair
Choose a moment when your child is relaxed. A tired or cranky child tends to curl their toes, and that can make the foot look shorter than it is. Many parents find that the end of the afternoon is easiest, because feet are often a little bigger after a day of activity. A song or a short video can also help with very young children.
Standing vs seated measurement
You can measure with your child standing or seated, and the difference matters.
Standing
Standing is the usual method for typical shoes. Place the paper on the floor with one edge against the wall. Ask your child to stand on the paper with their heel touching the wall and their weight on both feet. This shows the foot at its fullest length, because the foot spreads slightly under weight.
Seated
Some children, especially little ones or children who find standing still difficult, may be measured seated, with the foot flat on the paper and the knee bent at a right angle. If your child uses a wheelchair or cannot stand comfortably, seated measuring is a practical option. Be aware that a seated measurement can come out slightly smaller than a standing one, so leave extra margin when you choose a size, or ask us for help.
BILLY Footwear provides official videos showing how to measure standing, seated and over a brace; you can find them on our size guide page.
Measure both feet and use the longer one
Feet are rarely identical. One may be a little longer or wider than the other. Trace and measure both, and base the size on the longer foot.
- With your child's heel against the wall, hold the pen upright and trace around the foot, keeping the pen straight rather than angled under the foot.
- Mark the tip of the longest toe. This is not always the big toe, so look carefully.
- Remove the foot and draw a straight line from the back of the heel to the tip of the longest toe.
- Measure this line with your ruler in centimetres and note the figure.
- Repeat for the other foot.
Measure the widest part of the foot as well, across the ball of the foot. If your child has a wider foot, the width matters just as much as the length. If you are unsure, take a photo of the traced outline and send it to us.
Taking two measurements, a few days apart, is a sensible habit. If they match, you can trust the figure.
Add room for growth (and a brace if used)
A shoe that is exactly the length of the foot would be uncomfortable. Children's shoes need a little space at the front. A common rule of thumb is about a thumb's width of room beyond the longest toe, but how much extra length is right depends on the style, the age of your child and the shoe's design. We prefer not to give one number for every shoe, so treat the figure on your paper as the starting point and check the size guide or message us for advice.
If your child wears an AFO or another orthotic device, measure over the brace (or with the brace on, as your clinician advises) and consider width and depth, not only length. Braces take up room inside the shoe, so the size that works for a bare foot may not be the one that works with the brace. Our post on how to size adaptive footwear with confidence covers this in more detail. If you are unsure, ask your orthotist.
For children who grow quickly, avoid buying very large shoes "to grow into". Shoes that are too big can make walking less steady. It is usually better to buy the right size and plan to replace them.
Convert to EU/US with our size guide
Once you have your child's foot length in centimetres, you need to turn it into a shoe size. Different brands use different systems, and there is no single chart that fits all. For BILLY Footwear, use our size guide, which lists the matching US and EU sizes for toddlers, little kids and big kids. For example, it shows that EU 30 matches US 12 Little Kid. If your child's measurement falls between two sizes, we suggest asking us before you order.
For other brands, such as Princepard, check the size chart shown on that product page, as it may differ.
Frequently asked questions
How often should I measure my child's feet?
Children's feet change, so it is worth measuring whenever you are buying new shoes, and checking in between if shoes seem tight. Your paediatrician or podiatrist can advise on anything specific to your child.
Should I measure in cm or inches?
Centimetres are easier to work with because they match European sizing. Use whichever your ruler shows, but write it down clearly and convert accurately.
What if my child's feet are two different sizes?
Choose the size for the larger foot. If the difference is big or you are concerned, speak to your doctor or podiatrist.
Need help with sizing?
Once you have your measurements, browse our kids' collection. If you want a second pair of eyes, send the measurements to us through the contact page or on WhatsApp, and we will help you pick a size. Unworn items can be returned within 14 days of delivery.