No. 01 — CAD → Mesh · Free · No upload
STEP to STL,
in seconds.
Convert .step / .stp CAD files to STL mesh — ready for your slicer, 3D printer, or mesh editor. Runs entirely in your browser. Nothing is uploaded, ever.
.step / .stp
click anywhere · runs locally
(i)
Instant
Conversion completes in milliseconds — no upload, no queue, no waiting for a server. Your browser is the engine.
(ii)
Truly private
Your .step file is parsed and converted locally. No upload, no server log, no third party ever sees your geometry.
(iii)
Slicer-ready
Output is binary STL — accepted by Cura, PrusaSlicer, Bambu Studio, OrcaSlicer, and every 3D printing service.
§02 The problem
Got a STEP, need an STL.
CAD packages (SolidWorks, Fusion 360, Inventor, FreeCAD, Onshape) export .step — the precise B-Rep interchange format. But slicers and 3D printers only speak .stl — triangle meshes.
Slicer rejects it
Cura, PrusaSlicer, Bambu Studio won't open .step files directly.
Client sent the wrong format
You need to print, they sent CAD source.
Don't want to install CAD
Just to convert one file? Overkill.
→ This tool solves it instantly, in your browser.
§03 How it works
Three steps. No friction.
Step 01
Drop your .step file
Drag it onto the dropzone, or click to browse. Both .step and .stp are accepted.
Step 02
Convert locally
Your browser parses the STEP geometry, triangulates each face, and assembles a binary STL — typically under a second.
Step 03
Download the STL
Save the file and open it directly in your slicer, mesh editor, or 3D-printing service. Done.
§04 Why this tool
Free where others charge.
Most online STEP→STL converters upload your file, queue you behind a paywall, or cap file size. This one doesn't.
Zero cost
No subscription, no per-file fee, no credits to top up. Convert as many files as you want.
Zero latency
Conversion happens on your machine. No round-trip to a server, no upload bar, no queue.
Zero leak
Confidential geometry stays on your device. Safe for NDA work, client files, IP-sensitive designs.
Zero install
Works in any modern browser on macOS, Windows, Linux, ChromeOS. No plugin, no CAD license.
- < 1s
- Average conversion
- 0 bytes
- File upload
- None
- Sign-up required
- Binary STL
- Output format
§05 What people say
From makers, engineers and 3D-print shops.
“Exactly what I needed. Client sent a STEP from Fusion, I had to print it, and this converted it in a blink — without uploading proprietary geometry to some random server.”
Marc D.
Product designer · France
“I run a small print farm. STEP files used to mean opening FreeCAD just to export. Now I drop them in this page between jobs. Saved me hours per week.”
Priya S.
3D print service · UK
“The fact that nothing leaves the browser is a huge deal for our team. We can convert NDA-protected CAD files without going through IT.”
Tom V.
Mechanical engineer · NL
§06 FAQ
Everything else.
How do I convert a STEP file to STL?
Drop your .step or .stp file onto the converter at the top of the page. The conversion runs in your browser and gives you a binary STL to download — usually in under a second.
Is this STEP to STL converter really free?
Yes. Fully free, with no file-size cap from any server, since the conversion runs locally in your browser. No sign-up, no credit card, no per-file fee.
Are my STEP files uploaded to a server?
No. Your file is parsed and converted in your browser using JavaScript. Nothing is sent to any server, no logs, no analytics on your geometry. Safe for confidential and NDA work.
What's the difference between .step and .stp?
There is none — both extensions refer to the same ISO 10303 STEP format. This converter accepts either.
Will the STL open in Cura, PrusaSlicer or Bambu Studio?
Yes. The output is standard binary STL, accepted by every slicer (Cura, PrusaSlicer, Bambu Studio, OrcaSlicer, SuperSlicer) and every 3D-printing service.
Why won't my STEP file convert?
Most STEP files exported by SolidWorks, Fusion 360 or Inventor use NURBS surfaces, which require a CAD kernel to tessellate. This client-side tool supports planar / faceted STEP files. For NURBS STEPs, open them in FreeCAD or Fusion 360 and use the built-in mesh export.
Does this work on Mac, Windows, Linux?
Yes. It's a web page — it runs on any modern browser on macOS, Windows, Linux, and ChromeOS. No installation, no plugin.
Is there a file-size limit?
There's no server-side cap because nothing is uploaded. Practical limits depend on your machine's RAM and the complexity of the STEP file.
§ Ready
Drop STEP. Get STL.
Start printing.
Drag, drop, download. No upload, no queue, no cost — just your browser turning CAD into mesh.
Convert my file — free↑⚡ Free forever · No account · 100 % private