Fatima
Many thanks! 👋
STP to STL Converter: Free & Online
Convert single parts or full assemblies from .STP to .STL (Stereolithography) file format and prepare 3D models for printing in one app.
- Free account
- No install
STEP files are converted to a mesh on a MeshInspector server, so the web app asks you to sign in. A free account is enough.
How to convert STP to STL
Open the web app
Click Open in web app and sign in or create a free account. The web app needs it to convert STEP files on a MeshInspector server.
Open your .stp file
Click Open Files and pick the file. MeshInspector turns the CAD surfaces into a triangle mesh.
Export as .stl
Click Export, choose .stl in the Extension list and click Save. The file downloads to your computer.
In the desktop app
- Install and sign in. Download MeshInspector for Windows, macOS or Linux and sign in. The free Community plan is enough.
- Open the file. Click Open Files and pick the .stp file.
- Export. Select the model, click Export and choose .stl.
- Save. Pick a folder and save the .stl file.
What to know about STP → STL
- STP is the STEP CAD format under a shorter extension: exact surfaces and solids, not triangles. The conversion approximates curved faces with flat triangles.
- MeshInspector opens STP files but does not save them: the conversion goes one way, from STP to a mesh.
- In the web app an STP file is converted on a MeshInspector server, so you sign in with a free account, and the server deletes it automatically right after conversion; STL files are opened in your browser.
- An STP assembly opens as several objects. Export saves one object at a time: export the parts one by one, or combine them first in the desktop app.
- STP records units, STL has none, and slicers read millimeters: check the size of the STL in your slicer.
Online or desktop
Online
The MeshInspector web app opens STEP files after you sign in with a free account. No install is needed.
Desktop
The desktop app runs on Windows, macOS (Apple silicon) and Linux. Use it for large files, many files, and the tools the web app does not have. The free Community plan covers opening and exporting; see Pricing for what the paid plans add.
FAQ
Do I need an account to convert STP to STL?
Yes, a free one. A .stp file is converted to a mesh on a MeshInspector server, so the web app asks you to sign in; the free Community plan is enough. Then click Open Files, pick the file, click Export, choose .stl and save it.
Is the STP to STL converter free?
Yes. Opening STEP files and exporting the mesh as .stl are part of the free Community plan, in the web app and in the desktop app. Paid plans add tools such as Mesh Healer and automatic repair; the Pricing page lists what each plan includes.
Is my STEP file uploaded?
Yes. To turn the CAD surfaces into a mesh, the web app sends the .stp file to a MeshInspector conversion service, as the Privacy Policy describes. Mesh files such as STL, OBJ, PLY and 3MF are opened in your browser instead.
Are colors and units kept?
STL keeps only the triangles: colors, textures and units are lost when you convert to STL. STL has no units, and most slicers read the numbers as millimeters, so check the size of the model after conversion and use Scale if it is off by a factor of 10, 25.4 or 1000.
Is there a file size limit?
There is no fixed limit, but the web app works within your browser's memory: up to about 4 GB, or 16 GB in browsers with 64-bit WebAssembly. For large assemblies, or many files, use the desktop app for Windows, macOS or Linux.
Free Community planWindows, macOS (Apple silicon) and Linux
User Testimonials
By Mesh Inspector TeamPublished: Updated:
