Codex Custom Pet: How to Make Your Own Pixel Pet

What is a custom Codex pet?

A custom Codex pet is a pixel-art companion generated from your own photo or artwork, instead of a pre-made community pet. It carries your pet, your avatar, or your brand into OpenAI Codex.

Under the hood it is the same two files every Codex pet uses: spritesheet.webp (the animation frames) and pet.json (the config). The only difference is the source — you supply the image, the generator does the pixel art.

Why make a custom pet?

• Personal expression — a pet that actually looks like your cat, dog, or mascot
• Team identity — share one branded pet across your whole engineering group
• Recognition — spot your own companion instantly among community pets
• Fun — turn a meme, logo, or kid drawing into something that lives on your desktop

How to create a custom Codex pet (step by step)

Step 1: Open codexpetgenerator.com and click "Upload photo". Pick a JPG, PNG, or WebP with a clear, centered subject.

Step 2: The AI builds a pixel-art base in about 90 seconds. Approve the look, or regenerate for a different style.

Step 3: PetGen composes 9 animation states into spritesheet.webp + pet.json and packs them into a ZIP.

Step 4: Download the ZIP, unzip to a my-pet/ folder, copy it to ~/.codex/pets/, and fully restart Codex. Your custom pet appears and animates.

Customization options

You can steer the result by changing the source photo: different colors, a simpler background, or higher contrast all shift the final pixel pet.

On the Pro and Unlimited plans you can also edit pet.json directly — rename the pet, tweak the description, or adjust the spritesheet path.

Tips for the best custom pet

• Square crop close to 1:1 so the pet does not distort
• Keep the subject centered and the background clean
• Use at least 800x800 px so detail survives pixelation
• One clear subject works far better than a group shot