How to convert IGS to STP
- Add your .IGS file - drop it in the box above or click to browse.
- Convert it to .STP in a few seconds.
- Download your new .STP file.
What to expect
- IGES often stores trimmed surfaces that do not touch perfectly at their edges - gaps in the source become gaps in the exported STEP file; use FreeCAD Part > Sewing or Fusion's import healing to close them before re-exporting.
.stpand.stepare the same format - the extensions are interchangeable and the file contents are identical, so renaming is safe.- STEP comes in two common profiles: AP214 (default in most tools, supports color and layers) and AP203 (older, choose it only if a legacy system explicitly requires it).
Frequently asked questions
Are .stp and .step the same file?
Yes - both extensions refer to the ISO 10303 STEP format and the data inside is identical. You can rename
.stp to .step (or vice versa) without any conversion.Why does my converted STP file have gaps or missing faces?
The gaps were already present in the IGES source. IGES stores trimmed surfaces that may not close perfectly; use FreeCAD's Part > Sewing or Fusion's automatic import healing before re-exporting.
What is the difference between STEP AP203 and AP214?
AP214 adds support for color, layers, and assembly metadata and is the default in current tools. Choose AP203 only if an older system explicitly requires it.
Does converting IGS to STP lose any data?
Curved geometry (NURBS surfaces and solids) transfers accurately. What can be lost is color, layer names, and assembly hierarchy, since IGES rarely encodes these in a form STEP importers can read.
Programs that convert IGS: CATIA · Autodesk Inventor · SolidWorks · AutoCAD · TurboCAD · 3ds Max (3D Studio Max) · Autoconverter · Solid Edge
