Skip to content

.part file at a glance

Type

Temporary partial-download file

Created by

Browsers, download managers and file-sharing tools

Extension

.part

Standard

None, a naming convention

Can be opened

Usually not, the file is incomplete

CAD part files

.CATPart, .sldprt, .prt, .ipt, .par

  • Looking for a CAD part file instead?

    3D InterOp is an SDK that lets your application read native CAD part formats such as CATPart, SLDPRT, PRT, IPT and PAR.
Situation What happens

The transfer finishes

The temporary file is renamed or replaced by the final file

The transfer is paused or interrupted

The .part file stays on disk and the same application may resume the download, if both the server and the download manager support it

The file is renamed by hand

Missing data is not reconstructed: the file stays incomplete

  • Received data

    The bytes downloaded before the transfer stopped

  • No complete structure

    The end of the target format is usually missing

  • Tool-specific naming

    Each browser or download manager names its temporary files its own way

Extension What it is

.part

Temporary, partially downloaded file

.CATPart

CATIA V5 part

.sldprt

SOLIDWORKS part

.prt

Siemens NX or PTC Creo part

.ipt

Autodesk Inventor part

.par

Siemens Solid Edge part

  • A partially downloaded .part file falls outside what Spatial does. Our SDKs work with native CAD part formats, not with temporary download files.
  • Renaming the file to “finish” it

    Removing the .part extension doesn’t reconstruct missing data. At best, some media players open the portion already present.

  • Resuming with a different program

    Resume behavior is tied to the application that created the file, and depends on whether the remote server supports resumable transfers.

  • Confusing .part with a CAD part

    A .part file is not a 3D model. CAD parts use their own native extensions, such as .CATPart, .sldprt or .prt.

  • CATPart

    CATIA V5 part file
    CATPart
  • SLDPRT

    SOLIDWORKS part file
    SLDPRT
  • PRT

    NX and Creo part file
    PRT
  • IPT

    Autodesk Inventor part file
    IPT
  • PAR

    Solid Edge part file
    PAR
  • Product · 3D InterOp

    Read native CAD part files

    Import CATIA, SOLIDWORKS, NX, Creo, Inventor and Solid Edge parts into your own application.
  • Add CAD part import to your software

    Evaluate 3D InterOp on your own models with support from Spatial’s engineers.

Learn Valuable Insights on our Blog

9 Min Read
Insider
Meet Frédéric Jacqmin, VP of Worldwide Business Development at Spatial, bridging civil engineering roots and 14 years at...
3 Min Read
Manufacturing & Fabrication
We interviewed a Spatial client: COSCOM at EMO Hannover 2025. Thank you for your time Knut Mersch!
3 Min Read
Manufacturing & Fabrication
We interviewed a Spatial client: GO2cam at EMO Hannover 2025. Thank you for your time Eric Gerval!
12 Min Read
Insider
Meet Shad Reeves, Software Engineering Director at Spatial, leading a 42-person global R&D team behind one of the mo...
3 Min Read
Manufacturing & Fabrication
We interviewed a Spatial client: TopSolid at EMO Hannover 2025. Thank you for your time Patrice Tiberi!
2 Min Read
3D Modeling
Engineers spend over half their time prepping CAD data before the real work begins. Here's how digital continuity from d...