A shoe size chart converts or compares labels; it does not measure width, instep height, arch position, heel shape, or toe-box volume. It also does not know the last, materials, lacing, liner, insole, socks, intended activity, or the way a person prefers a shoe to feel. Use the table as a starting reference, not a guarantee of fit or comfort.
Age-based rows are estimates. Adult offsets, men's-to-women's shortcuts, and EU or UK rules are approximations. Rounding can place a foot near two rows, and a seller may define CM as foot length, recommended internal length, or another value. The shoe size chart cannot reconcile those definitions unless the product documentation explains them.
If a shoe is for a medical need, protective function, demanding sport, or specialized work, use the manufacturer's instructions and appropriate professional advice. This page does not certify footwear, assess a foot condition, or confirm that a model is safe for a task.