Woom vs Royalbaby

Both brands size kids' bikes by wheel diameter rather than frame size, so match the wheel to your child's height and inseam, not their age. A typical 4-to-6 year old (about 105-120cm tall) fits a 16-inch wheel on either brand; 6-to-8 year olds (120-135cm) move to 20-inch. The real fit difference is weight and reach: a Woom 16-inch bike weighs around 11-13 lb against roughly 17-19 lb for a comparable Royalbaby, and Woom pulls the bars closer for shorter arms. Measure standover first on both - the child should plant both feet flat over the top tube. If your kid is between sizes, Royalbaby's longer cockpit means sizing down keeps the reach manageable, while Woom's tighter fit lets confident riders size up sooner.