📏 Balance Bike Sizing Calculator
Wheel size is mostly marketing. The number that matters is inseam: the distance from your child's crotch to the floor, in socks or barefoot.
Measure once, ride forever
Stand the child against a wall in socks. Place a hardcover book firmly between their legs, spine up. Measure from the spine of the book down to the floor. That's the inseam.
Recommended seat height
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Set the seat at the bottom of this range when they first start (so feet are flat). Raise it as they gain confidence.
Recommended wheel size
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How the recommendation works
Seat height should be roughly inseam minus 2 cm (about ¾ inch) when first starting — feet completely flat on the ground. Once they're confident, raise seat to inseam minus 0 (feet flat with knees slightly bent) so they can stride efficiently.
Wheel sizes are a rough proxy:
- 10-inch: inseam 22-28 cm (typical 18-24 month olds)
- 12-inch: inseam 28-38 cm (2-4 year olds)
- 14-inch: inseam 36-44 cm (4-5 year olds, taller kids)
- 16-inch: inseam 42+ cm (rare on balance bikes — at this size most kids transition to pedals)
The seat-post range matters more than the wheel size — a good balance bike has 10-15 cm of adjustment so it grows with the child for 1-2 years.