A child rarely tells you a shoe is too small. They stop wearing it. The sneaker that was the favourite in June sits by the door in September and the child reaches for the sandals every morning, and it takes a parent a few weeks to work out why. This is the page for those weeks.
How often to check
Every six to eight weeks up to age three. Every three months after that. That's it. Put it on the calendar next to the dentist, because nobody remembers it otherwise, and a toddler's foot can grow half an EU size or more between two checks.
A European shoe size is a step of two thirds of a centimeter, a little over a quarter inch. That's small. A foot that grew one size doesn't look any different from across the room, and the shoe still goes on. It's the toes inside that know.
The thumb test, for a foot that won't hold still
Shoe on, child standing. Not sitting. A foot spreads under weight and a sitting measurement runs short. Press your thumb across the toe of the shoe. You're feeling for the longest toe, which isn't always the big one. There should be about a thumb's width between that toe and the end of the shoe, close to the centimeter of room a growing foot needs. Less than half a thumb and the shoe is done. Then press the sides: if the foot pushes the upper out over the sole, the shoe is too narrow whatever the length says.
Do it in the evening. Feet are bigger in the evening than in the morning, and a shoe that fits at breakfast can pinch at pickup.
Measuring the foot itself
Stand the child on a sheet of paper against a wall, heel to the wall. Mark the tip of the longest toe. Measure from the wall to the mark in centimeters. Do both feet. They differ. Buy for the bigger one. Then add the growing room: every children's shoe needs about half a centimeter to one centimeter of space in front of the toes, so a foot measuring 16.2 centimeters doesn't buy the shoe that's 16.2 inside, it buys the next one up.
Our EU to US kids shoe size guide has the chart that does this for you: foot length in centimeters in one column, the EU size to buy with growing room in the last one. Take the number from that last column, not the one that matches the bare measurement.
Why not two sizes up
Growing room is a centimeter. Not two. A shoe that's two sizes too big slides at the heel, and a child compensates by gripping with the toes, which is bad for the foot and turns walking into shuffling. On stairs it's a trip hazard. The extra months of wear you were buying come at the price of the shoe being wrong for the first two of them. One size of room, and a new pair when it's used up.
Signs the size is done
Red marks on the toes or the top of the foot when the shoe comes off. Toes that curl or sit on top of each other inside the sock. A heel that's red at the back. A child who suddenly wants the sandals in October, or who takes the shoes off at every chance. A shoe that has to be forced on where it used to slip on. Any one of these is enough. Measure that evening.
The opposite signs matter too. A heel that lifts out of the shoe with each step, a shoe that comes off in the sandbox, tripping on stairs: too big.
Brands don't agree on what a 27 is
An EU size describes the last the shoe is built on, not the foot. Shoo Pom, the French label on our shelf, builds each line on its own last, so its EU 27 runs from 15.7 centimeters in the Goa sandal to 17.0 in the Play boot. Cienta, the Spanish shoemaker from Arnedo, prints one chart for every style. That's why our Shoo Pom size chart is line by line and our Cienta size chart is one table. Measure the foot, then look up the brand, then pick the size. Never pick a size because it's the one the child wears in another brand. Brands differ.
Our own shoe stock runs from about EU 20 to 33 across sneakers, mary janes, boots and sandals, on the shoe shelf, with sneakers and sandals on their own pages.
Socks and the season
A shoe fitted in August over a bare foot is a different shoe in November over a wool sock. If the autumn shoes will be worn with thick socks, measure with the sock on. A thick sock changes the fit. Ours are on the socks and tights shelf.
Buying online without the shop floor
Most sizes on our shelf are here in one pair. We rarely restock, and there's no shop floor to try three pairs on. So the order goes: measure both feet in the evening, then look up the brand's own table by foot length. Where a chart lists the foot length a size fits, use the bare measurement and take the size that leaves the room. Where a chart lists bare sizes only, add the growing room from our chart first. If it comes back, return shipping is on you, which is why the measuring comes first. Send us the foot length and the shoe you're looking at and we'll measure the insole of the actual pair before you order.
How each clothing label on our shelf writes its sizes, which is a different problem from shoes, is on European kids brands size chart.