How to Convert SLDPRT to STL
SolidWorks SLDPRT files require a two-step conversion. Export to STEP in SolidWorks, then convert STEP to STL with our free tool.
Ready to Convert?
Export your SLDPRT to STEP in SolidWorks, then use our free STEP to STL converter.
Open STEP to STL Converter3 Steps to Convert SLDPRT to STL
Open in SolidWorks
Open your .sldprt file in SolidWorks. The part or assembly must be fully loaded.
Save As STEP
Go to File > Save As. Select STEP (.stp or .step) as the file type. STEP is a neutral CAD format that preserves geometry.
Convert STEP to STL
Upload the exported .step file to our free STEP to STL converter. Download the STL file for 3D printing.
SLDPRT vs STL Format Comparison
| Feature | SLDPRT | STL |
|---|---|---|
| Full name | SolidWorks Part | Standard Triangle Language |
| Maintained by | Dassault Systemes | Industry standard (1987) |
| Structure | Proprietary binary | Raw triangle list |
| Geometry type | Parametric (B-rep) | Triangle mesh |
| Design history | Yes | No |
| Configurations | Yes | No |
| Software support | SolidWorks only | Universal (all slicers) |
| Primary use | Mechanical CAD design | 3D printing |
| Open format | No (proprietary) | Yes |
What Is an SLDPRT File?
SLDPRT is the native part file format of SolidWorks (Dassault Systemes), a leading mechanical CAD (MCAD) application. SLDPRT files store parametric 3D models with features, dimensions, mates, configurations, and complete design history.
SLDPRT is proprietary and requires SolidWorks to open. To share models with non-SolidWorks users or convert to other formats, export to STEP (ISO 10303), which is the standard vendor-neutral CAD interchange format.
Last updated: August 2026. Format details reference the SolidWorks overview and the STL format overview.
Frequently Asked Questions
Can I convert SLDPRT to STL online?
Not directly. SLDPRT is SolidWorks' proprietary format and cannot be parsed by browser-based converters. Export to STEP in SolidWorks, then use our free STEP to STL converter.
How do I convert SLDPRT to STL in SolidWorks?
In SolidWorks, go to File > Save As. Select STL (.stl) as the file type. However, for browser-based conversion, first save as STEP, then use our STEP to STL converter.
Is there a free SLDPRT to STL converter?
SolidWorks has a free eDrawings viewer that can open SLDPRT files, but it cannot export STL. You need SolidWorks (or a STEP export from a colleague) to use our free STEP to STL converter.
Can I convert SLDPRT to STL without SolidWorks?
Not easily. SLDPRT is proprietary. If you don't have SolidWorks, ask the file author to export it as STEP or STL, which you can then convert or use directly.
Does converting SLDPRT to STL preserve dimensions?
Yes. When you export SLDPRT to STEP, all dimensional accuracy is preserved. Converting STEP to STL tessellates the precise surfaces into triangles with configurable resolution.
Can I convert SLDPRT to STL on Mac?
SolidWorks does not have a native Mac version. Use Windows (via Boot Camp or Parallels) to run SolidWorks, export to STEP, then use our online converter on Mac.
What is SLDPRT file format?
SLDPRT is the native part file format of SolidWorks (Dassault Systemes). It stores 3D CAD models with parametric features, dimensions, mates, and design history.
Why can't I convert SLDPRT directly in the browser?
SLDPRT is a proprietary binary format requiring SolidWorks' parametric kernel to interpret. No open-source parser can reliably read it. STEP export is the standard interchange path.
Can I batch convert SLDPRT to STL?
In SolidWorks, use Task Scheduler (included with SolidWorks Pro) to batch export multiple SLDPRT files to STEP or STL. Then use our converter for any STEP files.
What resolution should I use for SLDPRT to STL?
For 3D printing, use a deviation tolerance of 0.01-0.1mm depending on model size. In SolidWorks STL export options, set the resolution to 'Fine' or 'Custom' for best results.
Does SolidWorks eDrawings support STL export?
SolidWorks eDrawings (free viewer) can open SLDPRT files but STL export requires the Professional edition (paid). The free path is to use SolidWorks to export STEP, then convert.
What is the difference between SLDPRT and STEP?
SLDPRT is SolidWorks' proprietary format storing parametric features and design history. STEP (ISO 10303) is a vendor-neutral format storing precise B-rep geometry. STEP is the standard for CAD interchange.