# FBX files in browser games

## Go Bananas accepts FBX and converts it to GLB, keeping animations and shrinking textures to at most 512×512 pixels, so your game loads it like any GLB.

FBX is Autodesk's 3D format, widely used in game development and animation. It carries meshes, materials, skeletons and animations, and it is what services like Mixamo and many model stores hand out. Browsers can't read FBX well, which is why the site converts it.

## What FBX is good for in games

FBX is a common source format, especially for animated characters:

- **Rigged characters** with walk, run and attack animations.
- **Mixamo downloads:** a character plus separate animation files.
- **Assets from engines and stores** that only offer FBX.

On Go Bananas, every FBX becomes a [GLB](/formats/glb). Animations are kept. Textures are reduced to at most 512×512 pixels and saved as JPEG, which keeps games light but can soften detailed textures. If you can export GLB yourself with the texture sizes you want, upload the GLB directly.

## Uploading FBX to Go Bananas

You can upload in three places:

- **Create panel:** press the 📎 button or drag the file onto the chat.
- **Assets tab:** press **Upload Asset**.
- **Editor:** in the Assets tab press **Upload New**, press the 📎 in the editor chat, or drag the file onto the editor chat.

You need to be signed in with a verified email to upload.

| Limit | Value |
| --- | --- |
| Size per file | 200 MB |
| Total storage | 100 MB for free accounts created since May 5, 2026; 1 GB for Pro subscribers and older accounts |
| Uploads | 20 an hour per account |

Failed and deleted uploads don't count toward your storage. The site accepts binary FBX (starting with "Kaydara FBX Binary") and text FBX (starting with "; FBX"), and refuses empty files.

**What the site does with it.** The conversion runs in the background, so the model shows as processing for a moment.

- The FBX is converted to GLB.
- Animations are kept.
- Textures are shrunk to at most 512×512 pixels and saved as JPEG.
- The resulting GLB is then read like any GLB: its animation names, height, scale, orientation and position on the ground. The AI gets these details when it writes your game.

**FBX with textures, or several FBX files.** Put them in a [ZIP](/formats/zip):

- **One FBX with its textures:** it's converted with its textures.
- **Several FBX files:** they're merged into one GLB. The largest file is treated as the model and the others as its animations. This suits a Mixamo character plus animation clips downloaded separately.

When it's ready, you can open the model in the built-in 3D viewer and orbit around it. Asset cards show a thumbnail.

**The file name matters.** The name without its extension becomes the model's name in games: `wizard.fbx` is `"wizard"`. Renaming the asset changes the name, and code that used the old name won't find it. If two models share a name, the newest one wins.

## Using FBX in your game

**Ask the AI.** In the create box or the edit box, type `@` and pick your model. It inserts the name in quotes:

> Use "wizard" as the player; play its idle animation when standing and its run animation when moving.

**In code.** After conversion the model is a GLB, so it loads with three.js GLTFLoader, not an FBX loader. Its address is in `window.GAME_ASSETS.models['name'].url`. Go Bananas games use three.js r128 for 3D:

```html
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r128/three.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/three@0.128.0/examples/js/loaders/GLTFLoader.js"></script>
```

```js
let mixer, actions = {};
new THREE.GLTFLoader().load(GAME_ASSETS.models['wizard'].url, (gltf) => {
  scene.add(gltf.scene);
  mixer = new THREE.AnimationMixer(gltf.scene);
  for (const clip of gltf.animations) actions[clip.name] = mixer.clipAction(clip);
});
// in your animation loop: if (mixer) mixer.update(delta);
```

## Tips and common problems

- **Textures look blurry:** that's the 512×512 limit for converted FBX. For sharper textures, export GLB from your 3D tool and upload it instead.
- **Textures missing:** an FBX may point to texture files instead of embedding them. Zip the FBX with its texture folder.
- **Mixamo:** download the character "with skin" and the animations as separate FBX files, then zip them together. The merged GLB has one model with all the clips.
- **Huge FBX files** take longer to convert. Removing unused objects and cameras before export helps.
- **Deleting a model removes it at once**, so games that use it can no longer load it. A model can't be deleted while it's still processing.

## From ChatGPT or Claude

The Go Bananas app in ChatGPT and the connector in Claude can't send 3D files. Ask for an upload link and you'll get a link to the game's page, where you can upload the FBX in the editor.

## Related

- [GLB files](/formats/glb)
- [glTF files](/formats/gltf)
- [OBJ files](/formats/obj)
- [PLY splats](/formats/ply)
- [SPZ splats](/formats/spz)
- [ZIP bundles of 3D models](/formats/zip)
- [All file formats](/formats)
- [Making 3D games](/guides/3d-games)
- [How to make a video game](/guides/how-to-make-a-video-game)
- [Making games work on phones](/guides/games-on-phones)