Pixar's celebrating its 40th anniversary this year. For a good three quarters of that time, it's been a household name thanks to a series of blockbusters that have shaped the course of animation. And almost all of those films feature hidden references to where it all began.

From Toy Story in 1995 to this year's Toy Story 5, animators have creatively disguised a code in Pixar movies: A113. The studio's now provided the nearest thing we have to an official compilation of all the Easter eggs. How many did you spot?

The term A113 in Pixar movies is a hidden tribute to a classroom number at the California Institute of the Arts (CalArts), where many prominent Pixar directors and animators and studied graphic design or character animation. Alumni of that first-year classroom include Brad Bird, John Lasseter and Pete Docter.

This nostalgic nod to a shared alma mater appears in nearly every Pixar feature film like a kind of recurring graffiti. It's usually disguised in minor background details like licence plates, signage or other text. Sometimes the reference is in plain sight, while sometimes it's somewhat coded.

In Elemental, there's a sign that says "A H Al". Hydrogen has one proton and aluminium 13 – so A113. In Onward, there's a spoken A113 reference (a police officer speaks of having "a 113 in progress".

Other studios have sneaked A113 references into movies too, including Disney, Marvel and Warner Bros. Animation. There's even one in The Simpsons Movie.

Pixar's video above is not entirely definitive. It only goes up to 2024's Inside Out 2, and it misses Soul, Lightyear and Monsters Inc. Some movies also had multiple references. Among the more recent Pixar movies, there's an A113 in Toy Story 5 on the postcard Jessie finds from Emily, and the many Hoppers Easter eggs include "Idea #113" written on Dr Sam's chalk board (it's also the room number).

How many Pixar A113 references have you spotted, and where else have you seen the code?

Joe is a regular freelance journalist and editor at Creative Bloq. He writes news, features and buying guides and keeps track of the best equipment and software for creatives, from video editing programs to monitors and accessories. A veteran news writer and photographer, he now works as a project manager at the London and Buenos Aires-based design, production and branding agency Hermana Creatives. There he manages a team of designers, photographers and video editors who specialise in producing visual content and design assets for the hospitality sector. He also dances Argentine tango.