How to View a SolidWorks SLDPRT File Without SolidWorks

Direct answer: To view a SolidWorks SLDPRT file without SolidWorks, use Dassault Systèmes' free eDrawings Viewer, convert the file to STEP using an online converter and open it in a browser viewer, or ask the originating designer to share a STEP/IGES export. All three routes require zero SolidWorks licences and work on Windows, Mac, and mobile.

The Scenario Every Engineer Knows

A supplier sends over an SLDPRT file at 5 p.m. The design review is at 9 a.m. the next morning. The reviewer's workstation does not have SolidWorks installed — and a single floating licence costs upwards of ₹1.8 lakh per year. This is not an edge case; it happens in every manufacturing company where SolidWorks is used for design but the purchasing, quality, and production teams work without it.

The good news: several mature, free methods can open SolidWorks part and assembly files with no licence at all. This guide lays out each option with honest trade-offs so the right tool can be matched to the right situation.

Why SLDPRT Files Are Hard to Open Elsewhere

SolidWorks stores geometry in a proprietary binary format. Unlike STEP (ISO 10303) or IGES (ASME Y14.26M), SLDPRT is not an open standard, so third-party applications must either licence Dassault's translation engine or reverse-engineer the format. Most mainstream CAD tools — Fusion 360, CATIA, NX — can import SLDPRT natively, but they carry their own seat costs. The practical alternatives for zero-cost access are eDrawings, converter-based workflows, and browser STEP viewers.

The problem is amplified for assemblies. An SLDASM file references multiple SLDPRT files via local file paths. If the assembly is shared without all referenced parts in exactly the right folder structure, even eDrawings will show broken references. Planning the file-sharing step carefully saves a lot of frustration downstream.

Comparing the Main Options

Method 1 — eDrawings Viewer (Best for Working With the Raw File)

eDrawings Viewer is Dassault Systèmes' official free viewer and the closest experience to opening the file in SolidWorks itself. It reads SLDPRT, SLDASM, SLDDRW, DXF, DWG, and several other formats. The installer is roughly 400 MB and runs on Windows and macOS. Mobile apps are available for iOS and Android for on-the-floor review.

1. Download eDrawings Viewer from the official Dassault Systèmes website (search "eDrawings Viewer download" — the URL changes with each release).
2. Install the application. No SolidWorks licence file is needed; eDrawings is a standalone product.
3. Open the SLDPRT file via File → Open. For assemblies (SLDASM), ensure all referenced SLDPRT files are in the same folder structure the designer used, or pack-and-go was used to bundle them.
4. Use the View tab to orbit, section, and zoom. The Measure tool (available in eDrawings Pro — paid) adds distance and angle measurements. The free version allows orbit and section cuts.
5. Use File → Save As → eDrawings (.edrw) or PDF to share a view-only snapshot with colleagues who do not need to interact with the 3D model.

Limitation: eDrawings free does not generate a bill of materials. If the downstream task is procurement or FAI preparation, a STEP-based workflow is more practical.

Method 2 — Convert SLDPRT to STEP, Then Open in Any Viewer

This is the most portable workflow because STEP (ISO 10303-21, AP214 or AP242) is an open neutral format that any engineering software can read. Once in STEP, the file can be opened in browsers, sent to CNC programmers, imported into FEA tools, or uploaded to any cloud PDM system.

1. Ask the SolidWorks designer to export using File → Save As → STEP AP214 or AP242. AP242 is preferred for assemblies and includes PMI (Product Manufacturing Information) support per ASME Y14.41-2012.
2. If the designer is unavailable, use an online converter such as CAD Exchanger, AnyConv, or FreeCAD (open source) to convert SLDPRT to STEP locally. Upload the SLDPRT, download the .step output.
3. Open the resulting STEP file in a browser viewer — no installation required. CadNexa's 3D Viewer at cadnexa.com/app.html handles STEP and IGES files directly in the browser with a parts tree, measurement tools, exploded view, and section cut.
4. Verify the conversion by checking that all faces render correctly and no open shells appear. A clean STEP export from SolidWorks will show zero open edges in most viewers.
5. Share the .step file (or a viewer link) with any stakeholder. STEP files are typically 30–60% smaller than SLDPRT files because configuration and macro data are stripped.

For related reading on STEP workflows, see STEP vs IGES: Which CAD File Format to Use and How to Open a STEP File in Browser Without Software.

Method 3 — Autodesk Viewer for a Quick Browser Upload

Autodesk Viewer (viewer.autodesk.com) accepts SLDPRT and SLDASM uploads directly via a free Autodesk account. The file is converted on Autodesk's servers and rendered in the browser within 1–3 minutes for typical part files. Markup and measurement tools are available. The main constraint is a file size limit and the requirement for an internet connection, plus the fact that the file is uploaded to a third-party cloud — worth checking against any NDA or ITAR clause before use.

Method 4 — SolidWorks 3D Viewer Online (For Non-CAD Users in a Vendor Chain)

For situations where a purchasing manager or quality inspector needs to review a model without any technical background, the cleanest solution is a shared STEP link from a browser viewer. The recipient clicks the link, the model opens in the browser, and they can orbit, zoom, and check dimensions — no account required if the viewer supports guest access.

This pattern maps directly to what ISO 9001:2015 Clause 8.4.3 calls "communication with external providers" — ensuring that suppliers and customers have access to the technical data they need to do their job. A shared 3D link is faster and more reliable than emailing SLDPRT files that may not open on the recipient's machine.

Viewing SolidWorks Assembly Files (SLDASM) — Specific Considerations

Assemblies are harder than parts. An SLDASM file is essentially a manifest — it lists the component SLDPRT files by path. eDrawings requires the full folder tree to be present. The most reliable approach is to ask the designer to use SolidWorks Pack and Go (File → Pack and Go) which bundles all referenced components into a single zip. Alternatively, exporting the assembly as a single STEP file collapses all components into one portable file with the hierarchy preserved in the STEP product structure.

For procurement and production teams, the STEP export route is recommended. It eliminates broken-reference errors entirely and allows the assembly to be opened in CadNexa's 3D Viewer to generate an auto-BOM — useful when raising purchase orders or preparing for a First Article Inspection. See also STEP File BOM Export: Online Bill of Materials for a detailed walkthrough.

Common Mistakes and Pitfalls

• Sharing SLDASM without referenced SLDPRTs. The assembly file alone is meaningless; always bundle all components or export to STEP.
• Using an old eDrawings version. SolidWorks updates the SLDPRT format roughly every year. eDrawings from 2021 may fail to open an SLDPRT saved in SolidWorks 2024. Always use the latest eDrawings release.
• Uploading files covered by NDA to cloud converters. Run the conversion locally using FreeCAD or CAD Exchanger Cloud with your own account if the part is sensitive.
• Expecting full parametric data in a viewer. Viewers show geometry, not design intent. Feature trees, equations, and configurations remain inside the SLDPRT. This is fine for review but not for editing.
• Ignoring STEP version. AP203 (older) does not carry colour or layer data. AP214 carries colours. AP242 is the current standard and recommended for new workflows per ISO 10303-242.
• Not checking file units. SolidWorks parts can be in mm or inches. A STEP export preserves units, but some older viewers default to mm. Always verify a known dimension after opening to catch a unit mismatch before the file goes to production.

How CadNexa Helps

Once a SolidWorks file is exported as STEP or IGES, CadNexa's browser-based 3D Viewer opens it at cadnexa.com/app.html with a parts tree, auto-generated BOM with Indian material prices, measurement tools, exploded view, section cut, and wireframe mode — all without installing anything. For quality engineers moving from model review into FAI preparation, this removes an entire handoff step: the same platform that shows the 3D geometry also generates the First Article Inspection report in AS9102 Rev C, PPAP, or ISO formats.

Frequently Asked Questions

Can I open an SLDPRT file without a SolidWorks licence?

Yes. eDrawings Viewer (free, Windows/Mac/iOS/Android), Autodesk Viewer (browser, free with account), and online STEP conversion tools all let you view SolidWorks parts without any SolidWorks licence. For full measurement and BOM features, export to STEP and use a capable browser viewer.

What is the fastest way to view an SLDASM assembly file for free?

Ask the designer to export the assembly as a STEP file using SolidWorks' File → Save As → STEP AP214/AP242, then open it in any browser-based STEP viewer. This requires no software installation and works on any operating system, including Linux and Chromebook.

Can non-CAD users view SolidWorks files without training?

Yes. eDrawings Viewer and browser-based STEP viewers are designed for non-CAD users. Pan, zoom, and orbit controls take under five minutes to learn. Sharing a STEP link via a browser viewer is the lowest-friction option for purchasing managers, quality inspectors, and customers.

Does converting SLDPRT to STEP lose any data?

Geometry, part structure, and basic metadata transfer cleanly. SolidWorks-specific features — design tables, configurations, equations, and assembly mates — are not carried over to STEP. For review and measurement purposes, the STEP geometry is complete and accurate.

Is there a free online SLDPRT viewer that also generates a BOM?

CadNexa's browser-based 3D Viewer supports STEP and IGES files with an auto-generated BOM including Indian material prices. Ask your supplier to share the STEP export of their SLDPRT or SLDASM, then open it at cadnexa.com/app.html to get the full parts list instantly.

Conclusion

Viewing a SolidWorks SLDPRT file without a SolidWorks licence is a solved problem in 2026. eDrawings covers the native-file case with zero cost. For portability, sharing, and downstream workflows — BOM generation, vendor review, FAI preparation — converting to STEP and using a browser viewer is the more scalable choice. The STEP route also aligns with the industry trend toward neutral-format exchange endorsed by standards such as ISO 10303 and ASME Y14.41.

The only remaining friction is the conversion step itself, which takes about 30 seconds in SolidWorks. Once that export habit is established on the design side, everyone else in the value chain — purchasing, quality, production, and customers — can review models without any specialist software.