SLDDRW File — Open Without SolidWorks, Convert to PDF or STEP

Someone emailed you a .slddrw file. Or you found one on a shared drive and need to know what it contains. This post answers the practical questions: what .slddrw actually is, how it differs from SolidWorks’ other file types, how to open it without a SolidWorks license, and what data you can and can’t extract from it.

What is a .slddrw File?

.slddrw is the file extension for SolidWorks Drawing files. These are 2D technical drawings — the dimensioned, annotated sheets that engineers produce from 3D SolidWorks models to communicate manufacturing requirements.

The file contains:

• Drawing sheets (one or more, similar to tabs in a document)
• Drawing views — orthographic projections, section views, detail views, isometric views derived from the 3D model
• Dimensions — both model-driven (linked to the 3D geometry) and reference dimensions
• Annotations — notes, GD&T symbols, surface finish marks, weld symbols
• Bill of Materials (if the drawing includes a BOM table)
• Title block with part number, revision, material, drawn-by, and approval fields
• Cached 2D geometry — compressed vector data that represents the drawing views

The .slddrw file references one or more .sldprt (part) or .sldasm (assembly) files. Those 3D models are not embedded inside the .slddrw — they’re linked. When you open a .slddrw and the referenced model files aren’t available, SolidWorks uses cached geometry (introduced in the Detailing Mode feature in SW2020) to display the drawing.

The SolidWorks File Extension Family

The drawing (.slddrw) sits downstream of the models. You can have a drawing without the models if the cached geometry is present, but you can’t regenerate or update views without the originals.

.slddrw vs .sldprt vs .sldasm — How They Compare

The three main SolidWorks file types serve different roles and behave differently when the originating workstation isn’t available:

The assembly file size figures are often misleading. A .sldasm file that contains 500 components may be only 2 MB itself — all the geometry lives in the referenced .sldprt files. Sending just the .sldasm without the parts produces an unresolvable file. The .slddrw file has the same dependency: the drawing references the models but doesn’t embed them. The cached geometry (Detailing Mode) is a partial mitigation, not a substitute for the actual models.

What’s Actually Inside the File

SolidWorks drawing files use OLE Structured Storage as their container format — the same binary container that older Microsoft Office files (.doc, .xls) use. The file contains multiple named streams, including:

• Contents/DisplayLists__ZLB — compressed (zlib) 2D geometry cache for all drawing views. This is what SolidWorks Detailing Mode reads to display the drawing without loading the 3D models.
• Contents/SolidWorks_Drawing — the main drawing data stream containing sheet configurations, view metadata, and annotation data
• SummaryInformation — standard OLE property set with author, title, creation date

The cached 2D geometry uses CATIA’s internal primitive types — CATPrt2DSegment (lines), CATPrt2DArc (arcs), CATPrt2DBEZIER (spline curves), CATPrt2DPolyline (polylines). This is CATIA-inherited code that SolidWorks uses for hidden line removal and drawing projection.

For engineers who want to go deeper on the internals — including the hidden line removal pipeline and the swDrawingViewTypes_e enum — our post on SolidWorks drawing file internals covers the full decompilation findings.

How to Open a .slddrw File Without SolidWorks

Option 1: eDrawings Viewer (Free)

eDrawings is Autodesk’s free standalone viewer for SolidWorks files. It opens .sldprt, .sldasm, and .slddrw files without a SolidWorks license.

What you can do with eDrawings:

• View all sheets and drawing views
• Zoom, pan, rotate the 3D model embedded in the drawing (if 3D data is included)
• Measure distances on the drawing
• Export to image formats (PNG, BMP, JPEG) and to PDF (in eDrawings Professional, which is paid)

What you can’t do:

• Edit the drawing or add dimensions
• Export to DXF or DWG
• Access custom properties or the BOM data programmatically

eDrawings is available for Windows, macOS, iOS, and Android. For occasional viewing of received files it covers most needs.

Option 2: Online Viewers

Several online CAD viewers handle .slddrw files:

• 3DEXPERIENCE platform — Dassault Systèmes’ online viewer handles SolidWorks files natively. Free tier is limited.
• Autodesk Viewer (viewer.autodesk.com) — translates SolidWorks files in the cloud. Generally reliable for geometry but may drop some annotation types.
• ShareCAD, GrabCAD Viewer — community platforms that accept .slddrw uploads.

The limitation with any online viewer: the file is uploaded to an external server. For proprietary engineering drawings, verify your company’s data handling policies before using any cloud viewer.

Option 3: A Colleague with SolidWorks

If you need the drawing data in a usable format (PDF, DXF, or DWG), the fastest path is asking the SolidWorks user who sent the file to also export a PDF or DXF. SolidWorks can export directly:

• File → Save As → PDF — preserves annotations, title block, BOM tables
• File → Save As → DXF or DWG — exports the 2D geometry and annotations as editable CAD entities

For teams regularly receiving SolidWorks drawings and needing PDF or DXF versions, CadShift automates this export step — batch export from SolidWorks drawings to PDF with BOM quantities embedded, or to DXF with proper bend line and metadata handling.

File Size Expectations

.slddrw file sizes vary widely:

Large file sizes are usually driven by:

• High-resolution embedded graphics — if images are inserted (e.g., company logos, photos)
• Large assemblies — the cached display geometry for complex assemblies grows significantly
• Multiple sheets with complex annotations

If a .slddrw file is unexpectedly small (under 50 KB), it may be corrupted or contain only template data with no actual drawing content.

Can You Extract Data from a .slddrw Programmatically?

Yes, but only through the SolidWorks API (requires an active SolidWorks installation). The API provides:

• IDrawingDoc — top-level drawing interface
• ISheet.GetViews() — returns all views on a sheet
• IView.GetDisplayData3() — returns 2D geometry primitives (lines, arcs, text)
• IView.GetDimensions2() — returns all dimensions
• Custom property access via IModelDocExtension.CustomPropertyManager

Without SolidWorks running, there’s no official way to parse the binary stream and extract structured data. The OLE Structured Storage container is accessible via Microsoft’s compound file tools, but the internal streams are proprietary and undocumented.

The one exception: if the drawing was saved with the eDrawings publish option enabled, the .slddrw file includes an embedded eDrawings view stream that can be read by the eDrawings API.

Common Situations When You Encounter .slddrw Files

“A supplier sent me a drawing and I don’t have SolidWorks” Use eDrawings viewer to review it. Ask the supplier to also send a PDF for printing and dimensioned review, or a DXF if you need to import the 2D geometry into another tool.

“I need to import this drawing into AutoCAD” SolidWorks can export the drawing as DWG or DXF directly (File → Save As). The result is a flat 2D representation of the active sheet. The exported DWG will contain all visible geometry and most annotations, but parametric links and SolidWorks-specific objects (like BOM tables) become plain AutoCAD entities.

“I have a .slddrw but the parts files are missing” If the .slddrw was saved in SolidWorks 2020 or later and Detailing Mode is enabled, SolidWorks can still open and display the drawing using the cached geometry. eDrawings also works regardless of whether the referenced models are present. You can view and print the drawing, but views cannot be regenerated or updated until the models are available.

“I need to extract the flat pattern DXF from this drawing” The flat pattern DXF is generated from the .sldprt file, not from the .slddrw. If someone sends you a drawing of a sheet metal part and you need the DXF for fabrication, you need the part file — not just the drawing. See our guide on how SolidWorks creates flat patterns for DXF export for the full pipeline.

“The file won’t open in eDrawings — just a blank screen” This usually means:

1. The file version is newer than your eDrawings version — update eDrawings to match or exceed the SolidWorks version used to create the file
2. The drawing references Xrefs or embedded components that weren’t resolved when the file was saved
3. The file is corrupted — try opening in SolidWorks directly if available

Exporting from .slddrw — What Preserves What

For engineering workflows where you need to batch export DXF from SolidWorks drawings for fabrication — including bend lines, metadata layers, and proper flat patterns — this requires SolidWorks to be running and the referenced part files to be accessible.

Quick Reference

• Extension: .slddrw
• Created by: SolidWorks (Dassault Systèmes)
• Contains: 2D drawing sheets with views, dimensions, annotations, and optional BOM
• Free viewer: eDrawings (Windows, Mac, iOS, Android)
• Linked file types: .sldprt (parts), .sldasm (assemblies)
• NOT embedded: The 3D models are referenced, not stored inside the drawing file
• Can view without source models: Yes, if Detailing Mode cache is present (SW2020+)
• Editable without SolidWorks: No
• Export to PDF/DXF without SolidWorks: Not directly — requires SolidWorks or eDrawings Professional