Proper Bike Sizes for Children

Choosing the correct size bicycle for a child is important for her safety while riding. The correct bicycle is determined by wheel size, unlike an adult's bike, which is decided by seat height and frame size.

The Seat

When a child sits on the seat with his hands on the handlebars, he should be able to place the balls of both feet on the ground. When straddling the center bar, he should be able to stand flat-footed with about 1-inch clearance between his crotch and the bar.

Brakes

According to the International Bicycle Fund, coaster brakes may be easier for young children to use, but as a child gets older, bicycles with coaster brakes are less common. To determine whether a child is ready for hand brakes, she should be able to comfortably grasp the hand brakes and apply enough pressure to stop the bike.

2 to 4 Years Old

If a child's inseam measures 14 to 17 inches, the bicycle's wheel diameter should be 12 inches. Most of the bikes in this category come with training wheels.

4 to 6 Years Old

The second stage is when a child's inseam is 16 to 20 inches for a 14-inch wheel diameter. According to the International Bicycle Fund, these wheels are not commonly available.

5 to 8 Years Old

As your child gets taller, a 16-inch wheel diameter is needed. Your child's inseam would range from 18 to 22 inches. Most brakes with a 16-inch wheel diameter will have rear coaster brakes and pneumatic or solid tires, but some do have front hand brakes.

6 to 9 Years Old

Bikes with an 18-inch wheel diameter also are not widely available. The child's inseam would measure 20 to 24 inches.