About Sizeless

We make kids' shoes that grow with them.

Since 2023 we have been working on one idea: a kids' shoe with two sizes in one.

Two children playing with balloons, wearing Sizeless shoes

Why Sizeless exists

Children's feet grow fast. So a fixed size only ever fits for a moment.

On top of that, children don't notice when a shoe gets too small. And hardly any child likes the next trip to the shoe shop.

That's why we built a shoe that grows with them. Once the foot has grown, you simply move it on by one colour. So it always fits, and you need to go shoe shopping less often.

Our journey

From the first idea to the shoe on your feet.

March 2023
The idea wins

Our idea for a size-adjustable kids' shoe wins an Innovation Challenge by On.
June 2024
First prototypes

Together with experts from the German Sport University Cologne, we create the first prototypes that really work.
January 2025
On stage

We present Sizeless at startup competitions. The feedback and the prize money help us take the next step.
July 2025
Production partner found

With an experienced team, we develop the shoe until it is ready for production.
September 2025
Patent pending

Our size adjustment is protected by a patent application and a utility model.
July 2026
The first collection is here

Sprout, Reef and Galaxy. One shoe, three colours.

Six Sizeless kids' shoes in three colours on the grass

Developed with families

From the very start, families tested every prototype. Without their feedback, we would not be where we are today. Thank you to everyone who took part.

“The afternoon we picked up the parcel, my two girls didn't want to take them off. They love the shoes.”

Mum of two girls

The team

Louis and Leander, the founders of Sizeless

Louis

Co-founder, design

Our head designer. He makes sure the shoes are well thought out and comfortable.
Leander

Co-founder, partnerships

Keeps an eye on the big picture and connects Sizeless with important partners.