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Flip3D

STEP · STP · CAD Viewer

Online STEP Viewer

Drop a .step or .stp file to open it in a fast 3D viewer — drag to rotate, scroll to zoom, and inspect the CAD model. Free, instant, and 100% local: no CAD software and no upload.

No STEP handy?

About the STEP viewer

  • Opens STEP (AP203 / AP214 / AP242) and the .stp extension — the neutral CAD exchange format written by SolidWorks, Fusion 360, CATIA, Inventor and Onshape.
  • The B-rep solid is tessellated in your browser by an OpenCascade WASM engine, so the first file takes a few seconds to load the engine — after that it's instant.
  • Everything runs on your device. There's no upload, no account, and no file-size paywall — useful when the CAD file is under NDA.
  • This is a geometry viewer: it shows the shape, not the feature tree, dimensions or PMI annotations.
  • Need the model elsewhere? Convert the STEP to STL, OBJ, GLB, 3MF or PLY below.
STEP → STL
Convert this CAD file to a printable STL
STEP → OBJ
Convert to an editable OBJ mesh
STP Viewer
Same viewer, .stp extension

Frequently asked questions

How do I open a STEP file online?
Drop your .step or .stp file into the box above. It's tessellated and rendered right in the browser — drag to rotate, scroll to zoom. Nothing is uploaded and no CAD software is needed.
Is this STEP viewer free?
Yes. Completely free with no signup, no watermark and no file-size limit beyond 200MB. There's no trial and no paid tier.
What's the difference between .step and .stp?
Nothing — they're the same ISO 10303 format with two extensions. Older Windows software preferred the three-letter .stp. This viewer accepts both.
Is my CAD file uploaded to a server?
No. There is no server and no upload. The file is parsed and rendered entirely on your device, and nothing is stored — which is why it's safe for confidential parts.
Why does the first STEP file take a few seconds?
STEP is a B-rep (solid) format, so it has to be converted to triangles before it can be drawn. Flip3D loads an OpenCascade WASM engine once to do that; every file after it opens much faster.
Can I convert the STEP file to STL for 3D printing?
Yes. Flip3D converts STEP to STL, OBJ, GLB, 3MF and PLY in the browser. STEP is read-only here (there's no STEP export — mesh formats can't be turned back into real solids), but every mesh export is available. Convert links are by the viewer.