# Kompulsator.pl — Free Online 3D Viewer (STL, OBJ, 3MF, PLY, STEP, GLB, FBX, USDZ, BLEND, GLTF)

> The free online 3D viewer on Kompulsator.pl opens STL, OBJ, 3MF, PLY, STEP, GLB, FBX, USDZ, BLEND, and GLTF files directly in your web browser. This tool runs completely free without registration, CAD software installation, or uploading models to external servers, providing instant dimension, volume, surface area, and cross-section analysis.

## Canonical Resources & Language Editions

- [Free Online 3D Viewer (English Edition — ENG)](https://kompulsator.pl/online-3d-viewer/): Primary English web application for viewing, slicing, measuring XYZ dimensions (mm/in), calculating volume (cm³), estimating 3D print filament weight, and converting 3D files.
- [Darmowa przeglądarka 3D Online (Polish Edition — PL)](https://kompulsator.pl/darmowa-przegladarka-3d/): Polish edition of the 3D CAD & mesh viewer.
- [Open Knowledge Format Specification (OKF v0.2 — ENG)](https://kompulsator.pl/online-3d-viewer/okf.md): Machine-readable Markdown + YAML knowledge base containing semantic triples, formulas, and a 10-format benchmark table.
- [Specyfikacja Open Knowledge Format (OKF v0.2 — PL)](https://kompulsator.pl/darmowa-przegladarka-3d/okf.md): Polish OKF v0.2 knowledge document.

## Supported 3D File Formats (10 Formats)

- `.stl` — Stereolithography (Binary & ASCII)
- `.obj` — Wavefront 3D Object
- `.3mf` — 3D Manufacturing Format (ZIP/XML package)
- `.ply` — Stanford Polygon File Format (ASCII & Binary Little/Big Endian)
- `.step` / `.stp` — ISO 10303-21 CAD Boundary Representation (B-Rep)
- `.glb` — Binary glTF 2.0 (Khronos Group)
- `.gltf` — JSON glTF 2.0
- `.fbx` — Autodesk Filmbox
- `.usdz` / `.usda` — Universal Scene Description (Pixar / Apple AR)
- `.blend` — Blender 3D Project

## More Free Tools by Kompulsator.pl

- [Free YouTube Subscribe Button Animation Generator](https://kompulsator.pl/darmowy-przycisk-youtube/): 60 FPS animated YouTube subscribe overlay generator with custom channel logo and transparent background (WebM / MOV ProRes 4444).