Compare
STEP vs IGES
STEP and IGES are both used to exchange CAD data. STEP is a modern product-data standard; IGES remains in established workflows for geometry exchange. Choose for recipient requirements and verify units and the imported model.
Which format should you choose?
Prefer STEP for general 3D CAD exchange when the recipient has no requirement; use IGES when an existing workflow specifies it and validate the result.
Good fit for STEP
Cross-CAD 3D exchange
- Sending solid parts and assemblies to a partner using another CAD system
Good fit for IGES
CAD/CAM data exchange
- Existing workflows requiring IGES
Basic information
| Field | STEP | IGES |
|---|---|---|
| Extension | .step, .stp | .iges, .igs |
| MIME type | model/step | application/iges |
| Common uses | Cross-CAD 3D exchange | CAD/CAM data exchange |
| How to open | Open in a STEP-capable CAD viewer and inspect units, solids, surfaces, assemblies, and attributes. | Open it in a compatible CAD tool and check surfaces, solids, layers, and units. |
| Export or convert | After importing into native CAD, verify holes, surfaces, assembly structure, and units; feature history may not survive. | When converting to STEP, check surface gaps, solid creation, dimensions, and annotations. |
Choose by use case
Sending solid parts and assemblies to a partner using another CAD system
Cross-CAD 3D exchange
STEPExisting workflows requiring IGES
CAD/CAM data exchange
IGESKey point 1
STEP is the ISO 10303 product-data standard.
More on the differencesKey point 2
IGES is a long-used CAD/CAM exchange format.
More on the differencesMore on the differences
Confirm supported entities and units with the receiving CAD system. Inspect surfaces, solids, assembly structure, and dimensions after import rather than relying on file extension alone.
- STEP can exchange broader product model information depending on the application.
- IGES is often used for geometric entities in established workflows.
- Neither guarantees identical feature history across CAD applications.
Frequently asked questions
Is STEP always better than IGES?
Not for every workflow. Use the format the receiving system supports and inspect the converted geometry.