BREP (Boundary Representation) is OpenCascade's native solid-modelling format. It stores faces, edges, vertices, and topology, but no parametric construction history — what you see is what's there.

Where do BREP files come from?

Mostly FreeCAD intermediate files, OpenCascade-based pipelines, and academic CAD utilities. Mainstream commercial suites stick to STEP.

No. Files are opened entirely in your browser using local JavaScript and WebAssembly. Nothing is sent to a server.

Does it work on mobile?

Yes. The viewer is mobile-first and works on phones, tablets, and desktops.

CAD & PCB.brep · .brp

BREP viewer

ready

BREP · .brep · .brp

Open BREP files

Boundary Representation CAD geometry.

Choose a fileor paste · ⌘V

About BREP

Boundary Representation CAD geometry.

BREP is OpenCascade's native solid-model format — pure boundary representation with no parametric history. You'll see .brep files in OCCT projects, FreeCAD intermediates, and academic CAD code. We tessellate with OpenCascade compiled to WebAssembly and render the meshes with three.js.

FAQ

What is a BREP file?: BREP (Boundary Representation) is OpenCascade's native solid-modelling format. It stores faces, edges, vertices, and topology, but no parametric construction history — what you see is what's there.
Where do BREP files come from?: Mostly FreeCAD intermediate files, OpenCascade-based pipelines, and academic CAD utilities. Mainstream commercial suites stick to STEP.
Is my file uploaded?: No. Files are opened entirely in your browser using local JavaScript and WebAssembly. Nothing is sent to a server.
Does it work on mobile?: Yes. The viewer is mobile-first and works on phones, tablets, and desktops.

More CAD & PCB