How to Open 3MF Files in three.js
three.js is the most popular JavaScript library for 3D on the web, and it ships a loader for almost every common model format.
Short answer · Built in
Yes. three.js opens 3MF files as shipped: ThreeMFLoader from three/addons/loaders/3MFLoader.js.
Import 3MF into three.js, step by step
- 1Check the fileA 3MF is a zipped package that can contain several objects, colours and print settings; don't unzip it before importing.
- 2Import into three.jsThreeMFLoader from three/addons/loaders/3MFLoader.js.
- 3Check scale and orientationthree.js works in unitless (most scenes treat 1 unit as 1 metre) and is Y-up. 3MF files are millimetres, stored in the file, so they normally arrive at the right size.
- 4Check materials and animation3MF carries colours and print settings, and no animation. Look at the model under a neutral light before you build on it.
What comes through
| Shape | Yes, always. |
| Colours and materials | Yes: colours and print settings. |
| Textures | 3MF doesn't store texture images. |
| Animation | No: 3MF has no animation. |
Things to watch for
- Colours defined in the 3MF come through as materials.
- Compress big models with Draco or Meshopt and load them with the matching decoder; it can cut download size several times over.
Questions
- Does three.js support 3MF files?
- Yes. three.js opens 3MF files as shipped: ThreeMFLoader from three/addons/loaders/3MFLoader.js.
- Why is my 3MF model the wrong size in three.js?
- 3MF files are millimetres, stored in the file, while three.js works in unitless (most scenes treat 1 unit as 1 metre). Compress big models with Draco or Meshopt and load them with the matching decoder; it can cut download size several times over.
- What is the best 3D format for three.js?
- GLB and FBX are the most reliable choice for three.js. If you have a choice when exporting, pick GLB over 3MF.
Menu names follow the three.js open-source project's current release. Check the official three.js documentation if your version differs.
Written with AI assistance by the Renderlyst team in October 2026. Format support reflects each app's current release as we understand it, and we link the official documentation so you can confirm it for your version. Spotted something out of date? Email alishbakhalid766@gmail.com.