OBJ File Viewer

Open Wavefront OBJ files from Blender, ZBrush, scanners or AI generators with their colors and textures. Drop the .obj with its .mtl and images, or the whole folder as a .zip.

  • Files stay on your device
  • Free, no sign-up
  • Mesh check and printer fit
  • 14 formats

Drop an OBJ file to view it

or

STL · STEP · OBJ · 3MF · GLB · glTF · PLY · FBX · DAE · 3DS · AMF · IGES · VRML · ZIP

Opens on your device. Nothing is uploaded.

How to open an OBJ file online

  1. Open the file

    Drop the .obj with its .mtl and texture images, or a .zip of the folder.

  2. Check size and orientation

    The model stands on the plate in millimetres. Switch to inches, or change the file units or up axis if it looks wrong.

  3. Run the checks

    Read the mesh check, pick your printer to see whether it fits, and use Measure (M) or Section (X) for a closer look.

  4. Save or convert

    Take a PNG screenshot, or save the model as STL, 3MF, OBJ, GLB, PLY or USDZ.

What you can check in OBJ files

  • Materials and textures from the .mtl, or vertex colors written in the OBJ
  • Size in mm or inches, with a one-click fix for files made in metres
  • Triangle count, separate objects and a watertight check for printing
  • Wireframe and smooth shading to inspect topology
  • Save as STL, 3MF, GLB or USDZ

About OBJ files

An OBJ is plain text: vertices, faces, UVs and normals, with materials in a separate .mtl file that points at texture images. That split is why OBJs so often open grey: the viewer only got the .obj. Drop the .obj, .mtl and images together, or a .zip of the folder, and the viewer matches every reference by file name, even when the .mtl was written with absolute Windows paths.

OBJ has no units and no fixed up axis. The viewer assumes Y up, the convention of Blender and most 3D apps, and reads the numbers as millimetres. If the size looks wrong (a figure 1.8 mm tall was made in metres) it suggests a fix; switch to Z up if the OBJ came from CAD or a slicer.

OBJ at a glance

Wavefront OBJ · .obj

Stores
Vertices, faces (triangles, quads, n-gons), UVs and normals as text
Color
Materials and textures in a separate .mtl file; vertex colors as an unofficial extension
Units
None, the numbers are bare
Up axis
Y by convention (Blender, Maya, most 3D apps)
File size
Text: about a binary STL's size for bare geometry, up to twice that with UVs and normals
Opens in
Blender, Maya, 3ds Max, ZBrush, Cinema 4D, game engines, most slicers

OBJ came out of Wavefront Technologies' animation software and became the plain-text lingua franca of 3D. The geometry is in the .obj; colors and texture references live in a companion .mtl file, which is why OBJs so often arrive grey.

Tips for OBJ files

Grey model?

The .mtl or textures are missing. The note under Model lists the files the OBJ asked for, so you know what to add.

Lying on its back?

Switch the up axis to Z. OBJs exported from CAD and slicers are usually Z up.

Printing in color?

Convert to 3MF to turn material colors into filaments, or use the AMS converter for textured models.

OBJ viewer FAQ

Why does my OBJ show without textures?
OBJ keeps colors in a separate .mtl file and textures in image files. Drop all of them together, or zip the folder. The viewer matches files by name, so absolute paths in the .mtl are fine.

Can I open an OBJ file on my phone?
Yes. The viewer works in Safari and Chrome on iOS and Android. Zip the folder first to bring the .mtl and textures along.

What is the difference between OBJ and STL?
Both store surfaces. OBJ shares vertices and can keep UVs, normals, quads and materials; STL stores only loose triangles. Slicers read both, but STL is the safer choice for print services and OBJ for 3D apps.

Is the viewer free? Are there limits?
Free, with no sign-up, watermark or file limit. The practical limit is your device's memory: files of a few hundred MB open on most laptops.

Are my files uploaded anywhere?
No. Files are read by JavaScript and WebAssembly in your browser and never sent to PrintPal. Only the code is downloaded, and the STEP and IGES reader once, from a public CDN.