Skip to content
For software developers · 3D InterOp SDK

Convert NWD to VDA-FS in your application

3D InterOp is a CAD interoperability SDK that lets your software read NWD files and write VDA-FS, carrying across the exact geometry the NWD file contains.

Spatial does not offer an online converter or a desktop conversion app. 3D InterOp is a component that software vendors embed in their own products.

  • Reads Navisworks · Writes VDA-FS
  • Mixed geometry → exact geometry
  • C++ / C# APIs
project.nwdNavisworks · coordination model
Your application
3D InterOp SDK
Navisworks readerHealingVDA-FS writer
panel.vdaVDA-FS 2.0 · surfaces

NWD to VDA-FS at a glance

Navisworks can mix exact solids and facets; VDA-FS stores exact geometry. Exact elements are written as exact geometry, and elements stored only as facets stay faceted.

Navisworks (source)VDA-FS (target)
Full nameNavisworks document and cache filesVDA surface interface
Standard / ownerAutodeskVDA (German automotive industry)
File extensions.nwd, .nwc.vda
GeometryMostly tessellated, B-Rep for cylinder and elliptical shapesExact curves and surfaces
Assemblies / structureYesNo assembly hierarchy
3D InterOp supportRead onlyRead and write

What's preserved, what changes

Here is what your application can expect to carry across from Navisworks to VDA-FS.

  • Preserved
    Exact geometry
    Exact B-Rep read from NWD is written to VDA-FS as exact geometry.
  • Changes
    Assembly structure
    VDA-FS has no native assembly hierarchy. Decide in your application how Navisworks product structure is grouped or flattened before writing.
  • Changes
    Mostly faceted model
    Navisworks models are mainly read as visualization data; exact B-Rep is extracted only for cylinder and elliptical shapes.

Why software vendors add NWD to VDA-FS conversion

Legacy CAD and CAM systems

Many established engineering tools still consume VDA-FS first. Writing it lets your users hand data to them without leaving your application.

Supplier and partner exchange

Some suppliers and manufacturing partners still specify VDA-FS in their exchange requirements. Your software can meet them directly.

Geometry-only workflows

When a downstream process needs exact part geometry and nothing more, VDA-FS is a simple, widely readable target.

Things to check before you ship

  • Written VDA-FS versions: VDA-FS 2.0.
  • The VDA-FS writer isn’t available in 3D InterOp CGM.
  • Supported NWD input: Navisworks 2011 to 2026 (.nwd and .nwc).
  • Validate a sample of translated files in the target system your users actually work with.

Working with Spatial was a real milestone for us: Thanks to the powerful 3DInterOp library, we were able to successfully bring our complex CAD-based solutions to the cloud while remaining flexible to meet individual customer requirements. For us, Spatial is not just a technology partner, but a true enabler of our product strategy.

Dr. Arno Michelis, Founder, Simus Systems

Read the Case Study

About the formats

  • Source format

    What is a Navisworks (.nwd) file?

    NWD is Autodesk Navisworks’ document format, a compact snapshot of a coordination model that combines files from many design tools. NWC files are the cache files Navisworks creates when it opens a native file.

  • Target format

    What is a VDA-FS (.vda) file?

    VDA-FS is a neutral surface-exchange format defined by the German automotive association VDA. It stores exact curves and free-form surfaces, and is still found in automotive supply chains.

Frequently asked questions

The exact B-Rep that 3D InterOp reads from NWD is written to VDA-FS; parts stored only as facets stay faceted.

VDA-FS has no assembly hierarchy, so your application decides how the NWD structure is grouped or flattened before writing.

No. The VDA-FS writer isn’t available in 3D InterOp CGM.

Mostly not. Navisworks models are read as visualization data; exact B-Rep is extracted only for cylinder and elliptical shapes.

3D InterOp reads Navisworks 2011 to 2026 (.nwd and .nwc).

3D InterOp writes VDA-FS 2.0.

No. 3D InterOp reads NWD but doesn’t write it. To send data back to Navisworks users, write a format Navisworks opens, such as IFC.

  • Building software that needs to convert NWD to VDA-FS?

    3D InterOp is an SDK that lets your application read Navisworks and write VDA-FS alongside 30+ CAD and BIM formats.