Convert Parasolid
to 3DM.

Updated 2026-10-19

To convert Parasolid to 3DM, drop the .x_t or .x_b file into the converter below and download a .3dm that Rhino opens as NURBS polysurfaces: the solid's own faces, edges and trims, one polysurface per body, in millimetres. Fillets stay fillets you can measure and edit in Rhino. 5 conversions a day are free with no account. Rhino also imports STEP, so a STEP export from the sender is the other good route.

5 conversions a day with no account. No card, no install.

No account needed
Drop a Parasolid file.x_t / .x_b · up to 200 MB

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

ResultExact

Each body becomes one Rhino polysurface, and a closed solid stays closed, in millimetres. Every one is checked against Rhino's own validity test before it is written; a body that would fail it is written as a mesh instead, and the result says how many.

ChangesParasolid → 3DM

What changes between Parasolid and 3DM

Very little about the shape. A Parasolid transmit file describes a solid as faces on exact surfaces bounded by exact edges; a Rhino polysurface is the same idea written in NURBS. Every face, edge and trim is carried across, and a closed solid arrives closed, so Rhino calls it a solid and you can Boolean, fillet or section it straight away.

Each body is checked against Rhino's own validity test before it is written. A body that would fail it is not dropped: it goes into the file as a mesh instead, and the result says how many did.

What does not travel: there is no feature history on either side, colours and attributes are not carried, and the file has no layers beyond the default. .x_t and .x_b hold the same solid and give the same 3DM.

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

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.

Rhinoceros 3D model file (.3dm)

A 3DM file is a Rhino model. Rhino is a NURBS modeller, dominant in industrial design, jewellery, marine and architecture. A 3DM can mix exact breps, surfaces, meshes and curves on layers; polysurfaces and extrusions convert exactly, and mesh objects come along: as meshes in a mesh format, rebuilt as true surfaces in a solid one.

A designer works in Rhino and engineering or manufacturing needs the shape in a format their system reads.

Questions10 answered
Will the 3DM be NURBS or a mesh?
NURBS polysurfaces, one per body. Only a body that would fail Rhino's own validity test becomes a mesh, and the result counts them.
Do I need Rhino or a Parasolid licence?
Neither. The .x_t is read on our servers and the .3dm comes back ready for Rhino 7 and later.
Does an .x_b convert the same way?
Yes. .x_b is the binary encoding of the same solid and gives the same result.
What if the Parasolid file will not convert?
A few surface types, variable-radius blends among them, are not rebuilt yet. When the converter meets one it stops and names it rather than writing a damaged file, and the attempt does not count against your free conversions. Ask the sender for a STEP export instead; every Parasolid-based system writes one.
Is the Parasolid to 3DM converter free?
Yes. 5 conversions a day with no account and no card. A free account raises the limit and adds 25 credits.
Will the 3DM file keep exact curves and holes?
The 3DM file holds NURBS polysurfaces: the Parasolid solid's own faces, edges and trims. Each body becomes one Rhino polysurface, and a closed solid stays closed, in millimetres. Every one is checked against Rhino's own validity test before it is written; a body that would fail it is written as a mesh instead, and the result says how many.
Does it read both .x_t and .x_b?
Yes. Text (.x_t) and binary (.x_b) hold the same solid, and both convert here.
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 Parasolid 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 Parasolid 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 3DM to Parasolid.

Parasolid® is a registered trademark of Siemens. MeshWeave is an independent tool and is not affiliated with, endorsed by, or sponsored by Siemens. Rhinoceros® and Rhino® are registered trademarks of Robert McNeel & Associates. MeshWeave is an independent tool and is not affiliated with, endorsed by, or sponsored by Robert McNeel & Associates.