Ages + Stages

See Kai Run shoes are engineered to meet the different ages and stages of childrens' foot development.

agesstages.jpg

firstwalker.jpg

firstwalker.jpg

First Walker | Sizes 3 - 6

Crawling and First Steps | 9 - 18 Months

Foot: Bones form together and fatty pads minimize

Shoe Needs:
Flexible and lightweight
Outsole with added traction
Roomy toe box for healthy foot development
Wide openings with secure closures

toddler.jpg

toddler.jpg

Toddler | Sizes 4 - 9

Walking | 18 Months - 3 Years

Foot: Cartilage in foot begins to harden into bones

Shoe Needs:
Flexible and lightweight
Outsole needs ground traction for newly mobile child
Ample toe box room for development and movement
Some toe protection

preschool.jpg

preschool.jpg

Preschool* | Sizes 9.5 - 13.5

Running, Highly Mobile | 3 - 5+ Years

Foot: Bones fuse, fat tissue disappears and arch begins to form

Shoe Needs:
Flexible and lightweight
Traction to accommodate highly mobile child
Durability for active play
Wide openings with secure clsoures

*Select styles available in Grade School sizes 1Y - 4Y

Download our Printable Sizing Guide here.

See Kai Run Sizing Guide
This chart has acommodated for growing room.
If the foot measurement lands in between, order a size up.
Crib
LengthAge (approx.)Size
up to 9.7cm (3 7/8") 0-6 months Small
up to 10.9cm (4 3/8") 6-12 months Medium
up to 12.1cm (4 3/4") 12-18 months Large
First Walkers, Toddlers and Big Kids
If Your Foot Length IsYou Should Buy
CMInchesUS Size
10.5cm 4 1/8" 3
10.9cm 4 3/8" 3.5
11.3cm 4 1/2" 4
11.7cm 4 5/8" 4.5
12.1cm 4 3/4" 5
12.5cm 5" 5.5
12.9cm 5 1/8" 6
13.4cm 5 1/4" 6.5
13.8cm 5 1/2" 7
14.2cm 5 5/8" 7.5
14.6cm 5 3/4" 8
15.1cm 6" 8.5
15.5cm 6 1/8" 9
15.8cm 6 1/4" 9.5
16.2cm 6 3/8" 10
16.6cm 6 1/2" 10.5
17.1cm 6 3/4" 11
17.5cm 6 7/8" 11.5
17.9cm 7" 12
18.3cm 7 1/4" 12.5
18.7cm 7 3/8" 13
19.1cm 7 1/2" 13.5
19.6cm 7 3/4" 1Y
20cm 7 7/8" 1.5Y
20.4cm 8" 2Y
20.9cm 8 1/4" 2.5Y
21.3cm 8 3/8" 3Y
21.7cm 8 1/2" 3.5Y
22.1cm 8 5/8" 4Y