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STL to STEP converter
Turn a 3D printing mesh into a STEP solid you can open in your CAD program. Flat areas become real faces you can select, sketch on, and cut. Free, and the conversion runs on your computer.
About this converter
An STL file describes a part as thousands of tiny triangles, which is perfect for 3D printing but hard to work with in CAD. This converter turns it into a STEP solid: every flat area becomes a single face, with its holes and pockets as proper edges, so you can select faces, sketch on them, add features, and cut. Curved areas stay made of small flat faces, the way they were in the STL.
How do I convert an STL to a STEP file?
Drop your STL above, check the units, and choose Convert to STEP. The conversion takes a few seconds and runs on your computer. Enter your email address to download the STEP file, then open it in SolidWorks, Fusion, Onshape, FreeCAD, Inventor, or any CAD program that reads STEP.
Can I edit the STEP file in my CAD program?
Yes, as a solid body. Flat faces come through as real faces you can select, sketch on, extrude from, and cut, and the part has a true volume. Curved areas, like round holes and fillets, stay made of small flat facets, so you can't change a hole's diameter directly; cut a new hole through it instead. You won't get the original design history, because an STL never had it.
Is my file uploaded?
No. The conversion runs entirely in your browser, and your file never leaves your computer. We only ask for your email address before the download.
Is the STL to STEP converter free?
Yes. There's no charge and no account. We ask for your email address, and we'll send you our occasional email with tips on designing and making parts. You can unsubscribe anytime.
Why is my STEP part the wrong size?
STL files don't store their units. Most are in millimeters, but some are in inches. If the size shown before converting looks wrong, switch the units and convert again. The STEP file records its units, so your CAD program reads it at the right size.
Why is the STEP file so large?
A mostly curved part, like a sculpture or a 3D scan, has no flat areas to merge, so every triangle becomes its own face. Those files are large and slow to open in CAD. Parts designed in CAD, like brackets and enclosures, convert to far fewer faces.
Can you make my part?
Yes. Choose Get a quote to make this part to see a price in seconds for 3D printing, CNC machining, or laser cutting, or call us at (801) 613-1420.