Suitable for boys and girls from approx 2 1/2 years to 4 years. 12" is usually a child's first bike with driveable pedals and freewheel. A larger child in this age group may benefit from the slightly larger 14" wheel. These bikes usually come with training wheels which can be easily removed once your child has learnt to ride. Inside leg measurement are from 35cm to 42cm

Suitable for boys and girls from approx 3 years to 6 years. Like the 12" wheel bikes, 14" wheel bikes are usually supplied with training wheels. These bikes are for inside leg measurements from 40cm to 50cm.

Suitable for boys and girls from approx 5 years to 7 years. Once a child has learnt to ride without stabilisers (generally about age 5) they will move up to a 16" wheel cycle. These bikes normally come fitted with stabilisers but if not they can be added to virtually all 16" wheel bikes if required. This size of bike is available in a varity of styles including mountain bikes, traditional girls bikes and BMX bikes. Inside leg measurement for a 16" wheel bike is 40cm to 47cm.

Suitable for boys and girls from approx 6 years to 8 years. 18" wheel is the smallest bikes that come with multiple gears so you will see single speed and 6 speed bikes. Single speed bikes are simpler to use so may suit a child that is new to riding. Multiple geared bikes have a greater range and can cope with hills better. 20" wheel bikes are available in many "flavours", mountain bikes, traditional girls bikes and BMX style bikes, BMX bikes are always single speed. Inside leg measurement for these bikes falls between 45cm and 57cm.

Suitable for boys and girls from approx 7 years to 9 years. Once you get into the realms of 20" wheel bikes and above, you may be offered multiple frame sizes. This has the benefit of being able to fit a younger child onto a bigger wheeled bike if they are confident riders. Although you will find that size options are generally not offered on a particular model, rather that different models have different frame sizes. Inside leg requirement for 20" wheel kids bikes is between 55cm and 63cm.