Core 3D ViewerHow to open STEP files on iPhone
Take a CAD model from your files into a 3D view on your iPhone. Core 3D Viewer reads STEP and STP files on the device, so you can inspect a part or assembly without uploading it for conversion
Get the iPhone appFree download · iPhone, iOS 17+
Save the STEP file to Files
Save your .step or .stp file in the Files app on your iPhone. If it is in a cloud folder, download it before opening it offline
Import it into Core 3D Viewer
Open Library, tap +, and choose the file. The app imports the model and opens it in the viewer
Inspect the model
Rotate the model and zoom in to check the geometry. With Pro, use Dimensions to mark distances and Isolate to focus on parts and create saved views
Show the result to your client
Open Share and create a link. Your client can rotate the model and view the dimensions and saved views you included in a browser, without installing the app. Creating a link requires an internet connection
Before you start
Local import, optional online sharing
STEP conversion runs on your iPhone. Creating a share link is a separate action that uploads the model package so other people can view it
View CAD geometry on the go
Core 3D Viewer is a viewer and presentation tool. It does not edit a CAD model's original features or parametric history
Try the viewing experience
The pergola demo illustrates rotation, dimensions and saved views in the browser. It is a sample presentation, not a demonstration of importing a STEP file
Questions, answered
About STEP on iPhone
Can I open both .step and .stp files?
Yes. Core 3D Viewer accepts both filename extensions. STEP processing takes place on the device
Is STEP viewing free?
Importing and viewing models is free. Creating dimensions and managing isolated saved views on your own models requires Pro. You can try these tools for free on the included demo models
Can I see the model in AR?
Yes. Tap AR in the iPhone app to place a copy of the model in your space. AR displays the model without dimension annotations, so use the regular viewer or a share link to present measurements
Does my client need Core 3D Viewer?
No. A share link opens an interactive browser view without an app or sign-up. Anyone with the link can view it until it expires or you delete it