Drag a .3mf, .obj, .step or even a .png into the viewer, inspect it live, download a clean STL. Zero servers — your file never leaves the device.
100% local · file never leaves your browser
No upload limits, no email walls, no `your file is in queue position 47`. Just a drop zone, a viewer, and a download button.
Parsing & meshing run in WebAssembly + WebGL on your device. Nothing is ever uploaded.
Most files convert in under a second. No queue, no progress bar wishful-thinking.
Orbit, pan and zoom an interactive Three.js viewer before you download the STL.
Once loaded, the converter keeps running with no network — perfect for airgapped labs.
Toggle between compact binary STL (for slicers) and human-readable ASCII (for editors).
We don't cap files at 50 MB. The only limit is the RAM your browser is willing to give.
From 3D files to CAD assemblies to flat images — every format flows in or out of STL, in your browser.
Three.js loaders parse 3D formats, occt-import-js (WebAssembly OpenCascade) handles STEP/IGES, and a Canvas heightmap pipeline extrudes images. No server round-trip, ever.
3MF, OBJ, GLB, STEP, PNG, SVG and 10+ more formats. No size cap.
Live Three.js viewer — orbit, zoom, validate before you commit.
Binary or ASCII, named after the source. Send straight to your slicer.
STL Converter is built on Three.js, OpenCASCADE (WASM) and custom pipelines tested on thousands of real files. No server, no queue, no account to create — just an engine that runs in your browser.
From makers to engineers to prototyping studios — here’s what they say.
I convert STEP to STL for my 3D printer videos. Before I’d open Fusion, wait, export. Now it’s literally 3 clicks in the tab. Game changer.
The PNG → STL heightmap pipeline is clean. I send textures to clients as physical mockups, and STL Converter saves me a ton of time.
Airgapped lab, so no cloud tool is allowed. This one runs 100% local. 400 MB STEP files go through without a hitch. Exactly what I needed.
I use OBJ → STL to prep my sculptures before resin printing. The real-time 3D viewer lets me check I don’t have broken mesh before sending to the machine.
Not all my students have Fusion on their laptops. With STL Converter they can switch formats right in the browser. Zero setup, zero friction.
We receive files in every format. Having a single hub to normalize everything to STL — without uploading client data — is exactly the security level we were looking for.
No. Every conversion runs in your browser using WebAssembly and WebGL. The file handle stays in memory, nothing crosses the network.
Inbound to STL: 3MF, OBJ, GLB, GLTF, PLY, DAE, 3DS, FBX (read-only), STEP, STP, IGES, plus images (PNG, JPG, SVG) via heightmap extrusion. Outbound from STL: OBJ, GLB, GLTF, PLY, 3MF, SVG, GCODE.
STL is the universal slicer format. It's geometry-only, no colors or units — but every printer, every CAM tool and every mesh editor opens it without question.
Geometry: yes, vertex for vertex. Metadata (colors, materials, units, hierarchy) is dropped because STL doesn't carry it — this is a format limit, not a tool limit.
Whatever your browser's RAM allows. We've tested >500 MB models on a laptop. Nothing is uploaded, so there's no transfer bottleneck.
Yes for single conversions. A pro plan is planned for batch ZIP→STL, mesh repair and an API — but the core converter stays free, forever.
No account. No upload. Just a viewer and a download button.