Preview3D for macOS
Get

Changelog

What's new in Preview3D, release by release.

v1.0.0

First releaseComing soon to the Mac App Store

Viewing

  • Native macOS viewer (SceneKit / Metal) for STEP/STP, STL, OBJ, PLY, glTF/GLB, USDZ/USD, DAE, FBX, 3DS and 3MF.
  • STEP read via StepKit - a pure-Swift B-rep kernel with watertight tessellation and crease-aware normals (STEP viewing is in beta).
  • STEP per-part colors (STYLED_ITEM / COLOUR_RGB) rendered - colored assemblies show in their real colors.
  • Painted multi-material 3MF (PrusaSlicer mmu_segmentation) rendered in its filament colors, including sub-facet brush detail.
  • Turntable / arcball orbit, configurable background and optional floor.

Inspect & measure

  • Info panel with volume, surface area, centre of mass, watertightness, bounding-box dimensions and source unit for STEP.
  • B-rep structure (solids / faces / edges) and triangle / vertex counts.
  • Instanced assembly tree of sub-parts - repeated parts are placed at their true positions and share geometry; click a part to highlight and isolate it.
  • Centre-of-mass marker you can toggle on in the view.

PMI & GD&T (AP242)

  • Semantic PMI in the info panel: dimensions with ± tolerance bands, geometric tolerances (flatness, position, perpendicularity, profile…) with zones and datum references, and datum features.
  • Graphical PMI overlay - dimension lines, leaders and symbols drawn over the model, toggleable.

Finder integration

  • Quick Look previews for every supported format - including STEP, painted 3MF, FBX and 3DS that macOS can't render on its own.
  • Finder thumbnails via a dedicated thumbnail extension.
  • File-type association, Quick Look and thumbnails now cover the mesh formats read via Assimp (FBX, 3DS, X3D, LWO, MS3D, AC, AMF, OFF…), not just the core formats.
  • Heavy STEP previews and thumbnails use a fast coarse/decimated load, so large CAD stays quick in Finder.

Convert & export

  • One-click convert: STEP → STL / OBJ / GLB / USDZ (StepKit), any loaded scene → STL / OBJ / PLY (Model I/O).
  • USDZ output is ready for AR Quick Look.
  • Export a single selected sub-part of an assembly on its own.
  • PNG snapshots of the current view at 1×, 2× and 4×.

App

  • Apple silicon · macOS 14 Sonoma or later.
  • Built-in update check.