Convert BREP to OBJ
Convert BREP to OBJ in your browser. The conversion runs on this page and the file never leaves your computer.
Result
Before you convert: what this keeps and what it destroys
Preserved
- The shape, to within the tessellation tolerance
- Overall dimensions and proportions
- Watertightness, where the input is watertight
Destroyed
- Exact curves and surfaces, replaced by triangles
- The feature tree and any parametric history
- A recorded unit: OBJ stores none
Why people convert BREP to OBJ
Getting kernel geometry into a renderer, a texturing tool or an older mesh package, since OBJ is the one mesh format everything reads.
The exact surfaces are tessellated on the way through. Curvature decides the triangle count, so a bracket of flat faces produces a small file and a fillet heavy part produces a large one.
Two absences worth naming, and neither is this conversion's doing. BREP carries no colour, and the OBJ written here has no .mtl beside it, so the result is untextured at both ends of the trip. Neither format records a unit either, so the numbers are passed through as millimetres by convention and nothing is scaled.
What you get
You get a plain-text OBJ file you can open in an editor containing triangles. The reader tessellates supported surfaces or uses saved render meshes where required by the source format. Inspect curved faces at the intended output size. The triangle count depends on the model and the reader's meshing settings.
Not carried across by this conversion: a recorded unit.
The conversion runs in your browser. Your file stays on your computer and is not uploaded.
What to check afterwards
- BREP carries no unit. The numbers in the file are just numbers, so the conversion assumes millimetres. Check the overall dimensions of the result before you commit to machining or printing it. A file exported from a package set to inches will be 25.4 times out.
- The output keeps supported geometry and object names. The writer applies part transforms to the coordinates, without retaining the original transform hierarchy. It does not write material colours, texture coordinates or a companion material file.
- Curves become facets. BREP stores exact surfaces, so a hole is a cylinder with a radius. OBJ stores triangles, so that cylinder becomes a many-sided prism. Look at curved faces in the result at the size you intend to make the part.
If you need something this conversion cannot give you
If the unit has to be unambiguous, convert to 3MF instead. It records the unit in the file, so nobody downstream has to assume millimetres and nobody has to scale by 25.4 after the fact.
If you need editable CAD geometry, don't convert at all. Open the BREP file directly in FreeCAD, Fusion, Onshape or SolidWorks. Every mesh format destroys the exact surfaces, and no later conversion brings them back.
Going the other way
This site reads BREP but does not write it. For the reverse conversion, use an application that can export BREP.
How we know this conversion works
This pair was checked against 1 file from the test corpus on 2026-09-04. Each run parses its own output back in and compares the bounding box, the triangle count and, for closed solids, the volume against the input.
A pair that fails those checks doesn't get a page. That's why this site lists 120 conversions and not the several hundred a format-times-format grid would suggest.