Free Browser-Based STEP/STP Viewer for Quick CAD Inspection

[cadprops]

Hi everyone,

We're building CADProps, a free browser-based tool for quickly opening and inspecting STEP/STP files without installing a full CAD package.

It's aimed at mechanical engineers, CNC users, and manufacturing teams who need a fast way to check model geometry before quoting or production:
https://www.cadprops.com

Full disclosure: CADProps is our tool. We're still improving it, so feedback on real-world STEP files—especially large or complex models—would be very useful.

[SLW210]

Is this a free service?

[VicoWang]

Great work！！！

From a purely three-dimensional cross-sectional view, unlike the closed cross-sections of conventional three-dimensional software such as SketchUp, if the cut section after this trimming can be sealed off reasonably, it is at least visually more in line with intuition.

 

[cadprops]

On 9/18/2026 at 6:50 PM, SLW210 said:

Is this a free service?

 

On 9/18/2026 at 6:50 PM, SLW210 said:

Is this a free service?

Yes, it’s currently completely free to use.

If you think it could be useful to the CADTutor community, we’d really appreciate it if you could share it with other members or include it in any relevant CAD resources/tools section.

We’re also happy to keep improving it based on feedback from the community.

[cadprops]

On 9/18/2026 at 7:17 PM, VicoWang said:

Great work！！！

From a purely three-dimensional cross-sectional view, unlike the closed cross-sections of conventional three-dimensional software such as SketchUp, if the cut section after this trimming can be sealed off reasonably, it is at least visually more in line with intuition.

 

Thanks again for the feedback! We’ve already updated the section view so the cut faces are now properly closed, which should make the result much more intuitive.

If you find CADProps useful, we’d really appreciate it if you could share it with colleagues or others who might benefit from it. And of course, any further feedback is always welcome!

[SLW210]

I played with it for a few minutes, it needs better handling for .3mf files for me to have much use for it.

 

It only opened a few and failed to open several, all can open with my Bambu Labs Slicer.

 

The 10 MB limit is fairly low for 3D files, but for FREE, not too bad.

[cadprops]

Thanks for the detailed feedback! I’ve just improved the .3mf handling and fixed several compatibility issues.

Could you give those files another try when you have a chance? If any of them still fail to open, I’d really appreciate it if you could let me know.

Thanks again for helping me improve CADProps!

[cadprops]

12 hours ago, SLW210 said:

I played with it for a few minutes, it needs better handling for .3mf files for me to have much use for it.

 

It only opened a few and failed to open several, all can open with my Bambu Labs Slicer.

 

The 10 MB limit is fairly low for 3D files, but for FREE, not too bad.

Thanks for the detailed feedback! I’ve just improved the .3mf handling and fixed several compatibility issues.

Could you give those files another try when you have a chance? If any of them still fail to open, I’d really appreciate it if you could let me know.

Thanks again for helping me improve CADProps!

[SLW210]

That's better.

 

One about 7.5 MB file gave an error.

 

Quote

Mesh exceeds the triangle limit or contains non-finite coordinates.

Try a smaller model or split the assembly into separate files.

 

A few small 3.5 MB file

 

Quote

Temporary task capacity is full. Try again in about 1 minutes.

 

 

[cadprops]

SLW210, thanks for retesting and posting the exact messages. The two cases need to be kept separate:

The triangle-limit/non-finite-coordinate message concerns the mesh data, rather than just the compressed file size. That message alone doesn't tell us which condition your 7.5 MB file hit.

The temporary-capacity message concerns available processing capacity; it doesn't establish that the model itself is invalid.

I can't confirm that your original files now work. If either error still occurs, could you let us know which one, your browser/version and roughly when it happened? Please don't post a confidential model here. If you want to provide reproduction details privately, the support address is support@cadprops.com.

For context, CADProps reads core 3MF mesh geometry. Manufacturing extensions aren't interpreted, and mesh properties are approximate. Files are processed on the server, so please only upload models you're permitted to share with the service.

Disclosure: this is a CADProps team reply, written with AI assistance.

Current documentation: 3MF scope and limits