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. 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.