Open STL and 3MF Files Online
Drop a 3D model, turn it around with your mouse or finger, check its size, save a picture.
Binary and ASCII STL, and 3MF. Nothing is uploaded.
Drag to turn, scroll or pinch to zoom.
What you see here
STL and 3MF files are the two common formats for 3D printing. An STL is a plain list of triangles. A 3MF is a small zip package with the same kind of mesh, plus the size unit and sometimes several objects. This page reads the triangles and draws the model with simple shading, so you can check that the shape is right before you slice it. It does not repair meshes, slice, or show colours and textures.
Private: nothing is uploaded
The file is read inside your browser. It is never sent to a server, so your designs and client models stay on your device.
Questions
How do I open an STL file without a slicer?
Drop it on this page. You see the model at once, can turn it around and read its size. Nothing is installed.
How do I open a 3MF file online?
Drop it on this page the same way. The page reads the mesh inside the 3MF package, including the size unit, and shows all its objects together.
What size is my model?
The page shows the width, depth and height of the model. STL files do not store a unit, and most are in millimetres. 3MF files say which unit they use.
Why is my model not shown in colour?
This viewer draws the shape in one colour with simple shading. It does not read colours, textures or materials.
Is there a size limit?
Large models work, but very big files (hundreds of thousands of triangles) draw in a lighter way while you turn them and in full when you stop.
Is my file uploaded?
No. It is read in your browser and never leaves your device.