What is a .STEP file?
STEP is a standard CAD exchange format for precise 3D solid models, used across engineering tools.
- Did you know
- STEP (ISO 10303) was first published in 1994 as a universal CAD exchange standard.
- STEP stands for Standard for the Exchange of Product model data, the plain-language name behind the ISO 10303 number.
- A STEP file is human-readable text, with each geometric entity written on its own line and the whole model described against a referenced EXPRESS schema.
- Application protocols define what a STEP file may carry: AP203 covers basic geometry, AP214 adds colours and tolerances, and AP242 merges and extends both.
- Unlike a mesh format, STEP stores exact boundary-representation solids, so curves and surfaces stay mathematically precise rather than approximated by triangles.
- What Analyser shows you
- View STL, OBJ, PLY, OFF, STEP, IGES, BREP, 3MF, AMF and glTF/GLB models in an interactive WebGL viewer with orbit, orthographic or perspective projection, a wireframe topology overlay, an orientation cube, triangle count, bounding box, surface area and volume. glTF 2.0 and binary GLB scenes are parsed natively - the node graph is flattened, mesh geometry shown, and the authoring tool, version and mesh/material/animation counts read. STEP/IGES/BREP are tessellated with OpenCASCADE and STEP shows its originating CAD system, version and AP203/214/242 protocol; 3MF and AMF let you inspect each model and assembly on the build plate individually, and any pictures a 3MF package carries - its own thumbnail, the build-plate renders slicers such as Bambu Studio and OrcaSlicer write, and texture maps - are extracted and shown with it. Wavefront material libraries (MTL) are broken out into each material with its colours, shininess, opacity and the texture files it references.
- Open a .STEP file
- Drag a .STEP file onto the Analyser home page (or tap to pick one). It opens entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.