Online STL viewer
Drop your STL file and explore it instantly: real-mm measurements, wireframe and screenshots. The file never leaves your computer.
About the STL format
STL is the standard format of 3D printing: a triangle mesh with no explicit units, no color and no materials. It's mostly used for slicers (Cura, PrusaSlicer, Bambu Studio), FDM and resin 3D printing, CAD, and it stores geometry only (triangles and normals).
Frequently asked questions
Why doesn't my STL have colors?
The STL format only stores triangles: color, materials and textures simply don't exist in it. That's the price of its simplicity — for color, use PLY or GLB.
Binary or ASCII STL?
Both open the same here. Binary weighs ~5× less for the same geometry; ASCII only makes sense if you need to read the file with a script or edit it by hand.
What units is my STL in?
STL stores no units. The universal 3D-printing convention is 1 unit = 1 mm; if your part shows up 25.4× too small it was modeled in inches — the transform tool fixes that in one click.
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