3dfileconverter.onlineOBJ to STL Converter
Convert OBJ to STL online with a local 3D preview, unit controls and binary STL export. Files stay on your device; materials and textures are not included.
Enable JavaScript to open a model and use the interactive workspace.
How do I use this tool?
- Choose a OBJ file from your device.
- Preview your model and adjust the settings.
- Create your output and download the result.
What does this tool do?
STL stores triangle geometry only. Materials, colors and textures are not included. Conversion does not repair a model or guarantee printability.
What are the file limits?
Models are processed locally. Inputs are limited to 50 MB per file and 500,000 triangles after import. Individual operations may have lower limits described below. Performance depends on your device.
JavaScript, WebAssembly and WebGL are required for the interactive workspace.
How are models processed?
Mesh loading and rendering use Three.js. STEP import and tessellation use occt-import-js, based on Open Cascade. These sources describe the underlying libraries; this tool's supported features and limits are listed on this page.
Frequently asked questions
How do I convert an OBJ file to STL?
Open your OBJ file, select its source unit, and check the preview dimensions. Choose binary STL or enable ASCII STL, then select Export STL. The file is processed in your browser.
Will the STL keep my OBJ textures and colors?
No. STL stores triangle geometry, not textures or materials. This tool also does not load external OBJ material files or texture images. Keep the original OBJ and its companion files if you need their appearance.
Does converting OBJ to STL make the model printable?
No. Conversion does not close holes, repair non-manifold edges or check wall thickness. Inspect the mesh and check its dimensions in your slicer before printing.
Why is the converted model the wrong size?
OBJ and STL do not declare a reliable physical unit. Select the unit used for the original coordinates and the output unit expected by the next application. A mismatch between inches and millimeters changes the interpreted size by a factor of 25.4.