OBJ to STL File Converter: Free & Online

Convert 3D models from .OBJ to .STL (Stereolithography) file format and prepare for printing in one app.

Trusted by 10,000+ engineers
No Limits
Automatic Mesh Repair
SSL & Auto-Delete
Video coming soon

Read our step-by-step guide:

Which OBJ to STL Converter Is Best for You?

Compare OBJ to STL converters and find the best fit for your workflow.

MeshInspector App
MeshInspector Web
Other Converters
Speed
Ultra-fast Local processing
Fast
Slow
File Size Limits
Unlimited
Unlimited
File size limit (50 MB)
File Number Limits
Unlimited
Unlimited
Usually single file only
Folder Support
Full folder import
Full folder import
Not supported
Assembly Conversion
Partial or full assembly
Partial or full assembly
Not supported
Mesh Validation
Integrated
Integrated
Not supported
Auto Mesh Repair
Advanced
Advanced
Not supported
Mesh Repair Options
Advanced
Advanced
Not supported
Accuracy Control
Full
Full
Not supported
3D Viewer
Advanced
Advanced
Basic or no preview
3D Editor
Advanced
Advanced
Not supported
Security & Privacy
100% Local No upload needed
SSL + Auto-delete
Files often stored on servers
Cross-Platform
Windows, macOS, Linux
All devices
Web only, limited mobile UX
Suitable for
Professionals and engineers
Quick online conversions
Not recommended

Ready to Convert Your OBJ Files?

Join thousands of engineers who trust MeshInspector for their 3D file conversion needs. Start converting today with no limits and professional results.

How to Convert OBJ to STL with MeshInspector Software

MeshInspector can cover your needs when you are converting OBJ files to STLs. This step-by-step guide will show you how to change and export your OBJ model as a single STL file by relying on our program’s intuitive UI.

1

Opening OBJ Files

To initiate your quick and easy-to-perform conversion from the OBJ format to STL files, launch the MeshInspector program. Once it is up and running, go to the Home tab and click ‘Open Files’ to import your OBJ model, no matter how large it might be.

MeshInspector interface showing the Open Files option for importing an OBJ model.
2

Browsing OBJ Files

The program prompts you to select an OBJ. Click ‘Browse’, navigate, and confirm your choice. Note: if you are working on OBJ projects via the web version, they must be uploaded as zipped archives. On desktop, you can upload a single OBJ file.

File browser window displaying the selection of an OBJ file in MeshInspector.
3

Viewing OBJ Files

Once imported as a .ZIP, your .OBJ appears, ready for inspection. OBJ files may contain not only geometry but also textures and color data. MeshInspector can recognize all these, rendering them accurately. As a result, you are free to view the model from all angles.

3D crocodile OBJ model displayed in MeshInspector’s viewing window.
4

Exporting Components

We will now proceed to export our OBJ model to convert it into another format. Locate your model in the scene tree. Right-click on it to open the context menu, then select the ‘Export’ option.

Export menu in MeshInspector with the Export option highlighted.
5

Combining for Export

You can export several elements at once. Select what you are planning to export, right-click on them, then choose ‘Group’. After that, click on the resulting group and choose ‘Combine subtree.’ The tree can now be exported.

Combine Subtree option selected in MeshInspector’s right-click context menu.
6

Setting the STL format

In the dialog window, opt for STL from the ‘Extension’ dropdown. Then, our program will save your model in the STL format. Click ‘Save’ to complete the OBJ to STL conversion.

Save File dialog in MeshInspector showing STL as the selected file extension.
7

Inspecting the STL Size

Go to the ‘Inspect’ tab and select ‘Bounding Box’ to check your STL’s dimensions. All measurements will be displayed, making it possible to verify the eventual export scale.

Bounding Box measurements displayed in MeshInspector’s Inspect tab.
8

Adjusting the STL Size

To modify the STL’s scale and volume, use ‘Transform’ under the ‘Information’ section. Adjust the Scaling bar, apply changes by clicking on the checkmark, and verify the dimensions.

Transform panel showing scaling options for adjusting STL model size.
9

Finding ‘Mesh Healer’

MeshInspector includes the dedicated ‘Mesh Healer’ tool, located right under the ‘Mesh Repair’ tab. This helpful and potent feature is designed to automatically detect and, subsequently, fix geometry issues that may interfere with successful 3D printing. Using it ensures a clean surface.

Mesh Healer tool button highlighted in MeshInspector’s interface.
10

Fixing the STL File

Click ‘Mesh Healer’ to open a panel displaying all detected mesh problems: holes, flipped normals, non-manifold edges, zero-area triangles, or self-intersections. You can fix selected issues using ‘Local Repair’, or perform a full rebuild with ‘Auto Repair’, which reconstructs the mesh from scratch, in its entirety.

Mesh Healer repair panel showing detected mesh problems in a 3D model.

User Testimonials

4.9/5
out of 5 based on 2,547 reviews

Gabriele Impellizzeri

R&D Manager

MeshInspector significantly helped us in streamlining all of our 3D printing mesh modeling tasks thanks to its ability to fix, smoothly decimate and operate on our large-size lattice meshes in a fast and effective way.

Erick Geisler

Chief Technical Officer

"MeshInspector has completely transformed our workflow. It\'s faster, more efficient, and offers incredible value. The responsiveness of the development team and the quality of the software have given us a significant edge over our competitors."

Peter Sekula

Chief of Operations | Matterfield

"MeshInspector proves invaluable for 3D artists with its swift decimation and powerful Python API, streamlining workflows and enhancing efficiency. Its automation capabilities render it indispensable in the realms of gaming and VFX."

Daniel Gelep

3D Scanning Representative, Susteni AS

"It's the fastest program I\'ve used so far, and I can now do 150 scans in just 2 days instead of 1.5 weeks."

Ruedger Rubbert

Chief Technology Officer, Brius Technologies Inc

"With MeshInspector MeshLib we were able to automate many of our workflow processes, thanks to its advanced, modern, and efficient dental and geometry oriented algorithms, covering many of our orthodontic-related tasks: CT and intraoral scan segmentation, voxel and Boolean operations, editing, aligning, visualization, inspection, and import/export of mesh objects. We use the versatile MeshInspector MeshLib API, both in production and R&D for fast prototyping and testing of our ideas."

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