STL Viewer

Upload an STL and inspect the mesh.

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Binary and ASCII STL files are supported.
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What this tool does

Use this STL viewer to inspect binary or ASCII STL files locally in your browser.

When this tool fits

  • Best when checking slicer-ready mesh geometry

    the viewer shows the parsed STL mesh, triangle count, and dimensions.

  • Best for binary or ASCII STL validation

    a successful preview confirms the file can be read as STL geometry.

  • Best when units need a sanity check

    STL lacks unit metadata, so dimensions should be compared with the expected model size.

How to use it

  1. 1

    Upload an STL file

    Choose a binary or ASCII STL file from your device.

  2. 2

    Review the mesh preview

    Use orbit and zoom controls to inspect the visible model.

  3. 3

    Check size and triangle count

    Compare dimensions and triangle count with what you expect before printing.

Specs and limits

Input
Binary or ASCII STL
Output
Preview only
Shows
Mesh count, triangle count, and dimensions
Does not contain
Units, colors, textures, materials, or CAD history
  • STL has no units, colors, textures, or CAD history.

FAQ

Does STL contain units?

STL stores raw coordinates; units must be inferred from context.

Can this repair a broken STL?

No. The viewer helps you inspect whether geometry loads, but it does not repair non-manifold meshes or missing triangles.

Why does triangle count matter?

Triangle count gives a quick signal for mesh density. Very high counts can slow slicing, while very low counts may show faceting.

Related tools

STL Viewer - Inspect STL Mesh Geometry