Free STEP (.step, .stp) to STL (.stl) converter — running entirely in your browser. No upload, no signup, no file limits: your files never leave your device.
STEP · IGES · BREP · STL · OBJ · PLY · GLB · glTF · 3MF · COLLADA · AMF · FBX · 3DS · OFF
STEP is the industry-standard exchange format for parametric CAD data. It stores exact boundary-representation (B-rep) geometry — true curves and surfaces rather than triangles — which makes it the preferred way to move solid models between CAD systems like SolidWorks, Fusion 360, Inventor, CATIA and NX without losing precision.
STL is the de-facto standard for 3D printing. It describes a model purely as a mesh of triangles — no color, no units, no assembly structure — which makes it simple, universally supported, and the required input for virtually every slicer, from PrusaSlicer and Cura to resin-printer tools.
| STEP | STL | |
|---|---|---|
| Geometry | Exact B-rep solids & surfaces | Triangle mesh |
| Units | Yes, embedded | No — unitless numbers |
| Colors & materials | Per-part colors | No |
| Animations | No | No |
| Typical use | CAD exchange between engineering tools | 3D printing |
Yes — free with no accounts, no watermarks and no file-size limits. Conversion runs on your own machine, so there are no server costs behind it.
No. The converter runs entirely in your browser using WebAssembly. Your .step file never leaves your device, which makes it safe for confidential designs.
STEP stores exact CAD surfaces, which are tessellated into triangles at a quality you choose — from fast drafts to near-exact precision meshes. Preview the result in the built-in 3D viewer before downloading.
Yes. Every converted model opens in the built-in 3D viewer with an assembly tree, display modes and section views, so you can inspect the result first.
STEP stores exact boundary surfaces, but every output available here is a triangle mesh. Tessellation is irreversible: feature history, constraints and analytic curves cannot be recovered from the converted file. The STL result also has no units, colors, material data or part names, so keep the source alongside it.
A practical guide to converting STEP files to printable STL: tessellation quality, common pitfalls, and a free browser-based converter that keeps files private.
You received a .step or .stp file but have no CAD program installed. Here are your options — including a free browser-based STEP viewer that needs no install.
What do tessellation quality settings actually control? Linear and angular deflection explained with practical presets for 3D printing, rendering and web delivery.