STL, GLB, OBJ Explained: The 3D File Formats You Actually Need
Confused by 3D file formats? This guide breaks down when to use STL, GLB/GLTF, and OBJ — with real examples for 3D printing, web, AR, and modeling.
[Comparison infographic placeholder]
You've got a 3D model, but now you're staring at export options: STL? GLB? OBJ? GLTF? FBX?
Each format was built for a different purpose. Using the wrong one means broken viewers, failed uploads, or missing textures. This guide will help you choose the right format every time.
Quick Comparison Table
| Format | Best For | Textures | File Size |
|---|---|---|---|
| GLB/GLTF | Web, AR, E-commerce | Yes ✓ | Small |
| STL | 3D Printing | No ✗ | Medium |
| OBJ | 3D Software (Blender, Maya) | Yes (MTL) ✓ | Large |
GLB & GLTF: The Web 3D Standard
What it is: GLB (binary) and GLTF (text) are the modern standard for 3D on the web. Think of it as "the JPEG of 3D models."
✓ Use GLB/GLTF when you need:
- •E-commerce product viewers - Shopify, WooCommerce, custom stores
- •Mobile AR experiences - iOS/Android AR Quick Look
- •Interactive 3D websites - Three.js, Babylon.js, A-Frame
- •Fast loading times - Compressed binary format
- •Materials & textures - PBR materials included
Technical Details
- •GLB is binary (single file, smaller size) — use this for web/AR
- •GLTF is JSON + separate texture files — use for editing
- •Supports animations, PBR materials, and Draco compression
- •Native support in all modern browsers
[Screenshot: GLB viewer example]
STL: The 3D Printing Format
What it is: STL (STereoLithography) is the universal format for 3D printing. It stores only geometry — no colors, no textures.
✓ Use STL when you need:
- •3D printing - FDM, SLA, SLS printers
- •Slicing software - Cura, PrusaSlicer, Simplify3D
- •3D printing services - Shapeways, Sculpteo, i.materialise
- •CAD/CAM workflows - Manufacturing and prototyping
✗ Don't use STL for:
- •Web viewers (no textures or colors)
- •Product visualization (use GLB instead)
- •AR experiences (no material information)
Technical Details
- •Comes in Binary STL (smaller) and ASCII STL (human-readable)
- •Stores mesh as triangles only
- •Industry standard since 1987
- •Supported by every 3D printer and slicer
OBJ: The Universal 3D Format
What it is: OBJ (Wavefront) is the most widely supported 3D format across modeling software. It's human-readable text with optional material files (MTL).
✓ Use OBJ when you need:
- •3D modeling software - Blender, Maya, 3ds Max, Cinema 4D
- •Game engines - Unity, Unreal (though FBX is more common)
- •Cross-software compatibility - Everyone supports OBJ
- •Editing 3D models - Text format is easy to debug
Technical Details
- •OBJ file contains geometry (vertices, faces, normals)
- •MTL file contains materials (colors, textures, reflectivity)
- •Plain text format (can be edited in any text editor)
- •Larger file sizes than binary formats
Which Format Should You Use?
🛍️ For E-commerce & Product Websites
Use GLB — Fast loading, textures included, works on mobile AR, perfect for Shopify/WooCommerce.
🖨️ For 3D Printing
Use STL — Universal printer support, every slicer accepts it, geometry-only format is perfect for printing.
🎨 For 3D Software & Editing
Use OBJ — Works in Blender, Maya, 3ds Max, Cinema 4D, easy to edit and debug.
🎮 For Game Development
Use FBX or GLTF — FBX for Unity/Unreal with animations, GLTF for web-based games.
Converting Between Formats
Need to convert between formats? Here's what to know:
Free Conversion Tools
- •Blender (free) - Import any format, export to any format
- •Online converters - Quick but limited (watch file size limits)
- •Enviromn - Generate models with all formats included
⚠️ Conversion Warnings
- •STL → GLB: You'll lose color/texture data
- •OBJ → STL: Materials are stripped out
- •Always keep your original source file
Generate 3D Models in All Formats
Enviromn automatically generates your 3D model in GLB, STL, and OBJ formats. No manual conversion needed.
Frequently Asked Questions
Can I use GLB for 3D printing?
Technically yes, but most slicers prefer STL. Convert GLB → STL in Blender if needed.
What's the difference between GLB and GLTF?
GLB is binary (single file), GLTF is JSON + separate textures. Use GLB for web/AR, GLTF for editing.
Why are my OBJ textures not showing?
Make sure the MTL file and texture images are in the same folder as the OBJ file. OBJ uses relative paths.
Which format is best for Shopify?
GLB — Shopify's 3D model viewer uses GLB/GLTF format. It works perfectly for web and mobile AR.