Convert OBJ
to Parasolid.

Updated 2026-10-19

To convert OBJ to Parasolid, drop the .obj into the converter below and download an .x_t solid. Flat, cylindrical, conical, spherical and toroidal regions of the mesh are usually rebuilt as true surfaces, so a round hole becomes one cylindrical face; where none of those fits, the region becomes smooth patches or stays faceted, and the download says which you got. No account is needed for up to 2 solid conversions a day.

2 solid-geometry conversions a day with no account. No card, no install.

No account needed
Drop a OBJ file.obj · up to 200 MB
Several bodies

On our servers. No account: deleted within 24 hours. Signed in: kept until you delete them. Never shared or used for training.

ResultSurfaces recovered

Planes, cylinders, cones and spheres are rebuilt as true surfaces where the triangles fit them, and freeform regions as smooth patches, in a closed solid that mates, measures and cuts like modelled geometry. Where they cannot be rebuilt the body is faceted instead, and every conversion says which of the two you got.

The STEP as a faceted converter writes it: 524 flat faces, one per triangle.

One face per triangle · 524 faces. Each hole is a ring of flat strips you cannot select or measure.

The STEP from MeshWeave: 10 faces, 7 planes and 3 cylinders.

MeshWeave · 10 faces: 7 planes and 3 cylinders. The hole measures Ø12.00 mm.

The same 524-triangle STL, converted both ways and coloured one shade per face. A synthetic test part, run through the converter, not drawn.

Surfaces are only as accurate as the mesh they come from, and there is no feature history.

ChangesOBJ → Parasolid

What changes between OBJ and Parasolid

An OBJ is a graphics mesh: polygons, perhaps with texture coordinates and material names. It has no solid, no true curves and no unit. A Parasolid file is an exact solid. The conversion has to work out what surfaces the polygons were approximating.

Where a region of the mesh lies on a plane, cylinder, cone, sphere or torus, that surface is fitted and kept only if every vertex lies close to it; the region then becomes one true face. The faces are joined into a closed body that SOLIDWORKS, Solid Edge or NX can measure and mate.

Two limits matter with OBJ in particular. Models made for rendering are often not closed, with open edges, overlapping shells or single-sided walls, and such a mesh may come back as surface sheets rather than a solid. And sculpted or organic shapes have no simple surfaces to find, so they stay as patches or facets. Textures, materials and group names do not travel; the unit is taken as millimetres.

HowThree steps
  1. Drop your .obj file above — up to 200 MB without an account.
  2. Parasolid is already selected as the output.
  3. Download the .x_t. Without an account, files are deleted within 24 hours; signed in, they are kept until you delete them.
FormatsWhat you are holding

Wavefront OBJ file (.obj)

OBJ is a plain-text mesh format from graphics. Unlike STL it keeps named groups, texture coordinates, materials and polygon faces, which makes it the usual handover into rendering and texturing tools. It is still a mesh, not a solid.

The destination is a renderer, game engine, texturing tool or visualisation pipeline.

Parasolid transmit file (.x_t / .x_b)

Parasolid is the modelling kernel under SOLIDWORKS, Solid Edge and NX, and a transmit file is its exact solid geometry. Between systems that share the kernel it often survives better than a neutral format. .x_t is text, .x_b is binary; both hold the same solid.

Someone in a Siemens or SOLIDWORKS shop sent you an .x_t and nothing you have opens it.

Questions10 answered
What unit does the OBJ need to be in?
OBJ records no unit, so its numbers are read as millimetres. Scale the model before converting if it was made in metres or inches.
Will a game or render model convert into a solid?
Only if the mesh is closed. Render models are often open or built from overlapping pieces, and those come back as surfaces rather than a solid.
Do I get an .x_t or an .x_b?
An .x_t, the text encoding, which is what SOLIDWORKS, Solid Edge and NX users usually exchange. The binary .x_b holds the same solid at the same precision; the encoding makes no difference to the geometry.
Should I convert to STEP instead?
For any CAD system other than SOLIDWORKS, Solid Edge or NX, yes. The recovered surfaces are the same either way.
Is the OBJ to Parasolid converter free?
Yes. 2 solid-geometry conversions a day with no account, of 5 in total. A free account converts 4 solid files a day and adds 25 credits. No card.
Does the Parasolid result have real curves, or flat facets?
The mesh comes back as a Parasolid solid with real surfaces: a round hole becomes one cylindrical face. Planes, cylinders, cones and spheres are rebuilt as true surfaces where the triangles fit them, and freeform regions as smooth patches, in a closed solid that mates, measures and cuts like modelled geometry. Where they cannot be rebuilt the body is faceted instead, and every conversion says which of the two you got. Surfaces are only as accurate as the mesh they come from, and there is no feature history.
Will the Parasolid file open in Fusion 360, Inventor or Onshape?
Yes. Parasolid is read directly by Fusion 360, Inventor, Onshape, SOLIDWORKS, Creo, NX and FreeCAD. It usually arrives as a solid body with true surfaces, without feature history, and the conversion says when it came back faceted instead.
How big a file can I convert?
To a mesh format like STL: 300 MB with a free account, 200 MB without one. To STEP, Parasolid or SLDPRT: 140 MB, because rebuilding a solid takes about twice the memory of writing a mesh. Maker and Studio convert up to 830 MB and 380 MB — a large conversion on a paid plan gets the server to itself.
Is it safe to upload my OBJ file?
Files travel encrypted and are processed by machine on our own servers — no third parties, no ads or trackers, no AI training.
Is my OBJ file deleted after converting?
Without an account, the upload and the result are deleted within 24 hours. With an account, both stay in your files until you delete them; deleted files leave our servers within 24 hours.
Beyond convertingSame file, four workspaces

Keep the part open: fill it with a lattice, check it with FEA, texture a surface, or slice it into cut-ready sheets. These workspaces are in early access — create an account, then apply from inside the app.

Create free account See pricing

AlsoOther ways in
MoreRelated conversions

Going the other way? Convert Parasolid to OBJ.

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