CADProps · CAD tools

CATPart Viewer Online: Open CATIA V5 Part Files

Open CATIA V5 CATPart files online from the geometry CATIA saved, check dimensions and convert to STEP. CATProduct files show only their saved thumbnail.

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Capabilities and limits

Open CATIA V5 CATPart files online from the geometry CATIA saved, check dimensions and convert to STEP. CATProduct files show only their saved thumbnail.
Exact results need a complete B-Rep that matches the saved display; otherwise properties are approximate. CATProduct shows only its saved thumbnail.
Files are uploaded for server processing; support depends on format, version and geometry.
Viewing and measuring do not require an account. Sign in to convert, save files across devices or create share links.
CATDrawing drawings show only their saved preview image: unknown units, no drawing-content reading, 3D geometry, measurement or model conversion.

On this page

Open a CATIA V5 CATPart without installing CATIA. CADProps reads the part in-house and shows the display geometry CATIA saved with it. When the part's B-Rep is reconstructed completely and matches that display, exact properties and exact STEP export are available; otherwise dimensions and properties are approximate.

What you see after upload

Most CATPart files show their saved display triangles within seconds. A part saved without display geometry shows the thumbnail stored in the file instead, with no 3D measurement. Check orientation, the expected bodies and one known dimension before using the numbers.

Exact and approximate results

The result states whether the geometry is an exact B-Rep or an approximate mesh. Exact results support B-Rep edge and diameter measurement, and volume and surface area from the solid. Approximate results give overall size and mesh-based values; treat volume and mass from them as estimates.

Exact reconstruction does not yet work for every CATPart, so many parts open with CATIA's saved display geometry only. That is enough to identify a part, check its overall size and spot a wrong revision, but not to quote a bore diameter or a machined volume. When the result says approximate and you need exact values, ask for a STEP export from CATIA rather than re-uploading the same CATPart.

Check a CATPart before it goes to a supplier

Compare the overall size with the drawing. The plate in the screenshot below was modelled as 8 × 6 × 0.5 in and reads 203.2 × 152.4 × 12.7 mm; switch the unit display to inches to compare it directly with an inch drawing.
Confirm the expected number of bodies. A part that should be one solid but shows several pieces, or shows surfaces only, needs a look in CATIA before anyone quotes it.
Read volume and mass only from a closed solid. A part built from open surfaces still has a size and an area, but no meaningful volume.
Note whether the result is exact or approximate in the handoff, so the receiver knows which numbers came from the solid.

CATProduct assemblies

A CATProduct upload shows only the thumbnail saved in the file; CADProps does not assemble its parts in 3D. To review the parts, upload the CATPart files individually. For the whole assembly, ask for a STEP export from CATIA.

Convert CATPart to STEP

Sign in and choose STEP in Convert. You get an exact STEP when the part's B-Rep is complete, and a mesh STEP otherwise. Neither restores CATIA sketches, constraints or the feature tree. CATPart to STEP explains the difference.

CATPart to STL, OBJ or 3MF

After signing in, Convert also offers STL, OBJ, 3MF, GLB and glTF. These files are built from the triangles you see in the viewer. For a part shown from CATIA's saved display, the facet density is whatever CATIA used when the part was saved, so curved faces may look coarser than a print or render needs. Zoom in on fillets and holes before you print; if the facets are too coarse, ask for an STL exported from CATIA with a finer tolerance.

When a file will not open

CATIA releases and saved data vary, and compatibility with every release is not established. Do not rename the file. Confirm the source release and request a fresh STEP export when needed. CATShape, CGR and CATIA V4 MODEL/SESSION are not supported. 3DXML exports with XML or CATIA V5 binary (UVR) .3DRep tessellations have a separate 3DXML viewer: approximate meshes with unverified units, without exact B-Rep.

CATDrawing: the saved preview image

Upload a .CATDrawing to see its saved preview, when present. The image can help identify the attachment, but CADProps does not read drawing views, dimension entities or title-block data. There is no 3D rotation, measurement, exact property calculation or model conversion from this image; its physical units are unknown. If the saved image is missing or too small for review, ask for a PDF, DXF or DWG export. Request the CATPart or a STEP export for 3D geometry.

Input formats: CATPart / CATProduct / CATDrawing (saved image only)

Open this tool

General steps for uploading, viewing, sectioning, measuring, converting and exporting are explained once in How it works. This page covers what is specific to this file type.

Real CADProps screenshots

The screenshots show the English interface. Captions and instructions describe the same operations.

Properties — SS_PL_8x6x0.5_B.CATPart · 203.2 × 152.4 × 12.7 mm · 393,289.604 mm³ · 70,967.61 mm² This native preview is evidence for the pictured file and version only. It does not establish universal compatibility, exact B-Rep measurements or successful STEP conversion.

Sample source and verification

When a result needs another check

Viewing can start without an account. Conversion, account storage and share creation require signing in. Temporary files expire after the displayed retention period. Read the privacy statement for server processing and deletion, and the accuracy notes before using numerical results. Do not assume that hiding a part, clipping it or exploding an assembly changes the exported source geometry.

When a result needs another check · Input formats

Continue with a related task

Original article: CADProps · https://www.cadprops.com/tools/catia-viewer/

Try a CATPart Example

Download the public CATPart plate from BatchProcess, then select Choose file above. This third-party sample is provided under its MIT license; it is not a CADProps-authored model. The separate Try a real sample button loads a STEP bearing.

After processing, rotate the plate and open Properties. The independently checked sample contains one solid, measures 203.2 × 152.4 × 12.7 mm and has a volume of 393,289.536 mm³. Confirm units before using these values. Mass depends on the selected density.

CATPart plate displayed in the CADProps workspace with its measured dimensions and volume — Actual workspace capture using the linked public plate; this test does not establish compatibility with every CATIA version.

How to open CATPart files without CATIA explains the complete workflow and what to check when processing fails.

A reproducible example

Public NIST CTC01 saved by CATIA V5-6R2019 displayed a converted mesh, approximately 800 × 450 × 150 mm. Properties are approximate and do not establish B-Rep accuracy or universal version compatibility. See the guide for the actual screenshot and CSV.

Repository-generated samples are synthetic test models. Verify your own model's units and geometry before using results.

Supported formats

All formats and limits →

STEP STEP · STPExact B-Rep
IGES IGES · IGSExact B-Rep
VDA-FS VDA · VDAFSDisplay geometry
IFC IFC · IFCZIPMesh
SolidWorks SLDPRTB-Rep when readable
Autodesk Inventor IPTB-Rep when readable
Parasolid X_T · X_BExact B-Rep
Siemens NX PRTDisplay geometry
Solid Edge PAR · PSM · ASMDisplay geometry
Autodesk Fusion F3DDisplay geometry
Creo Neutral NEUDisplay geometry
STL STLMesh
OBJ OBJMesh
GLB GLBMesh
X3D X3D · X3DVMesh
UNV UNVMesh
U3D U3DMesh
PRC PRCMesh
G-code GCODEToolpath lines
AutoCAD DWG · DXF2D view

Questions about this task

Can I open a CATPart file without CATIA?

Yes. Upload the CATPart to see the display geometry CATIA saved with the part. Parts saved without display geometry show their saved thumbnail.

Can I open CATProduct assemblies?

Not in 3D. A CATProduct shows only its saved thumbnail. Upload the CATPart files individually, or ask for a STEP export of the assembly.

Are CATPart measurements exact?

Only when the part's B-Rep is reconstructed completely and matches the saved display; the result says so. Otherwise dimensions, area and volume are approximate values from the display mesh.

Can I measure CATPart geometry online?

Yes. Verify units and a known dimension before relying on calculated area, volume or density-based mass.

Can I convert CATPart to STEP?

Yes, after signing in. You get exact STEP when the B-Rep is complete and mesh STEP otherwise. STEP does not restore CATIA's parametric features.

Can I inspect a CATDrawing file?

A CATDrawing can show its saved preview image. Drawing views, dimensions and title blocks are not read. Physical units are unknown, with no 3D geometry, rotation, measurement, exact properties or model conversion. Request PDF, DXF, DWG or the source model when no usable preview is saved.