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OBJ to STL

Convert OBJ 3D models to binary STL locally - ready for 3D printing and any slicer. No upload.

Running locally on your device ...

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Your files never left your device

    Is my file uploaded?

    No. Everything runs in your browser - your file never leaves your device. How this is verifiable

    No upload100% local
    Your content stays with youno third-party access
    Servers in GermanyGDPR by design
    Independently auditedTLS A+ · HTTP headers A+

    OBJ (Wavefront) is a common 3D exchange format from programs like Blender, Cinema 4D or MeshLab. For 3D printing, however, slicers such as Cura, PrusaSlicer or Bambu Studio usually expect STL - the plain triangle shell of a model. This tool reads your OBJ and writes a compact binary STL you can load straight into the slicer.

    Faces with more than three corners (quads or larger polygons) are split into triangles during conversion, since STL knows only triangles. For each triangle the face normal is additionally computed and written out. The result is binary STL, because it is markedly smaller than the text variant and is read by every slicer.

    Everything runs entirely locally in the browser - your possibly confidential model never leaves your device. Honestly framed: pure geometry is transferred. OBJ material (MTL), textures, texture coordinates and groups have no counterpart in STL and are not carried over. An invalid or empty OBJ file is rejected with a clear message.

    Specifications

    Specifications
    Input formatsOBJ
    Output formatSTL
    Batch processingNo
    ProcessingLocally in your browser (JavaScript)
    File uploadNone

    In 3 steps

    1. Drop your OBJ file.
    2. The conversion runs automatically.
    3. Download the STL (for 3D printing).

    Limitations: Converts OBJ to compact binary STL: quads and larger polygons are split into triangles, and a normal is computed per triangle. Pure geometry is transferred - OBJ material (MTL), textures and groups have no counterpart in STL. An invalid or empty OBJ file is rejected with a clear error.

    FAQ

    Binary or ASCII STL?

    The tool writes binary STL because it is markedly smaller and read by every slicer. If you need text, use the reverse direction via STL ASCII to binary.

    Are quads supported?

    Yes. Quads and larger polygons are automatically split into triangles, since STL knows only triangles.

    Are material and texture kept?

    No. STL stores geometry only; material (MTL), textures and texture coordinates have no counterpart there.

    Is my file uploaded?

    No, the conversion happens entirely locally in the browser; your model never leaves your device.

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