About this tool
This calculator maps a child's measurements to children's clothing sizes in the US, EU and UK systems, all in your browser with nothing uploaded. Enter the child's age, height and optional weight; height is the most reliable guide, so it drives the result while age acts as a fallback and weight as a tiebreaker.
EU children's sizes are based directly on height in centimeters, stepping through standard increments (50, 56, 62, 68, 74, 80, 86, 92, 98, 104 and up), so the tool finds the nearest EU size for the height entered and reads the matching US label (Newborn, 0–3M through 24M, then 2T–6T and 7–16) and UK age band from the same chart. If you provide a weight that is high for the height, it nudges the recommendation up one size.
Growth varies a lot between children, so use the age range shown to sanity-check the fit rather than relying on age alone. When a child is between sizes, the larger size usually gives more wear before it is outgrown.