STEP Model Viewer
Open and inspect step files directly in your browser. No installation.
ISO 10303 CAD tessellation for assemblies and parts.
Drop your STEP file here
Upload a STEP or STP CAD file or ZIP package to inspect your engineered geometry.
Open STEP Assemblies Without a CAD License
STEP is the ISO 10303 standard most CAD tools use to exchange parts and assemblies, but opening one usually means owning the CAD software that made it. GLBKit tessellates STEP and STP geometry locally with OpenCascade, so you can check assemblies, individual parts and CAD-stored colors in the browser without a CAD license.
OpenCascade Tessellation
Tessellates STEP CAD geometry locally in the browser using OpenCascade.
ISO 10303 Standard
Reads AP203, AP214 and AP242 STEP files as exported by common CAD tools.
Inspect Assemblies
Step through multi-part assemblies, individual parts and CAD-stored colors.
No CAD License Required
Get a quick visual check on a .step or .stp file without opening CAD software.
GPU-Accelerated Preview
Renders tessellated CAD geometry smoothly.
Viewer Only
Built for inspection, not editing — and no upload needed to look at a part.
About this format
STEP (Standard for the Exchange of Product Data) is the ISO 10303 standard for exchanging CAD data between tools. It captures exact B-rep geometry, product structure, and metadata from SolidWorks, Fusion 360, CATIA, Siemens NX, and Onshape. GLBKit renders .step and .stp files in the browser so you can review CAD geometry without a CAD licence.
What is a .step file?
.step (also .stp) is a text-based CAD exchange format defined by ISO 10303. It describes exact B-rep geometry, product structure, tolerances, and metadata in a single file.
STEP is the universal CAD exchange format, supported by every major CAD tool. It is the safest way to share geometry between vendors.
- ISO 10303 text-based CAD exchange format
- Stores exact B-rep geometry, product structure, metadata
- Universal exchange between SolidWorks, Fusion 360, CATIA, NX, Onshape
- Preserves tolerances, materials, and product structure
Common uses for STEP files
STEP is the standard for CAD data exchange. Every mechanical engineer and product designer uses STEP to share geometry between vendors and tools.
- CAD exchange between vendors and toolchains
- Long-term archival of product geometry
- Manufacturing handoff and supplier collaboration
- Engineering review and tolerance analysis
How GLBKit renders .step files
GLBKit tessellates the STEP geometry in the browser and renders the resulting mesh with WebGL. The tessellation is a visual approximation of the exact CAD geometry.
- Drop a .step or .stp file to start
- Orbit, pan, and zoom with mouse, touch, or pen
- Tessellated mesh rendering of B-rep geometry
- No upload, no signup, fully local processing
GLBKit capabilities for .step
GLBKit renders the visible geometry of a STEP file as a tessellated mesh. It is a viewer for review, not a CAD editor: you cannot modify geometry or product structure.
- Tessellated B-rep rendering for visual review
- Inspect product structure and metadata
- Verify geometry before manufacturing handoff
- Process files locally in the browser
Who uses GLBKit for .step files
STEP is the daily format of mechanical engineers and product designers. GLBKit is the fastest way to open a STEP file without a CAD licence.
- Mechanical engineers and product designers
- Manufacturing engineers reviewing supplier geometry
- Quality and inspection teams
- Students learning CAD exchange
Open your .step file now
Drop a .step or .stp file into the viewer. Inspect CAD geometry in seconds.
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How to Open STEP Files Online
Learn how to open, view, and inspect STEP and STP CAD files online using the GLBKit STEP Model Viewer.
- Upload your STEP fileDrag and drop your .step or .stp file into the GLBKit viewer or click the upload button to select a STEP file from your device.
- Tessellate the CAD geometryGLBKit processes the STEP file in your browser and tessellates the CAD geometry into meshes.
- Inspect the 3D geometryRotate, zoom, and pan around the STEP model to inspect the tessellated geometry from different angles.
- Review CAD colors and assembliesInspect supported CAD colors and multi-part assemblies rendered as separate meshes.
- Preview your CAD assetView the STEP model directly in your browser without installing dedicated desktop CAD software.
Related guides
Frequently Asked Questions
Common questions about opening STEP and STP CAD files in the browser.