How to convert IGES to STL
- Drop your .iges file into the box above, or click Choose file.
- Check the 3D preview, size and triangle count.
- Make sure STL is selected as the output format. Adjust scale or up-axis if needed.
- Click Download. The .stl file is created instantly on your device.
Why convert IGES to STL?
IGES is an older CAD exchange format that slicers cannot read. The converter tessellates its surfaces into triangles for printing or visualisation.
What changes in the conversion
- Surfaces become triangles. IGES stores exact curved surfaces; STL stores a triangle mesh. Curves are approximated with a fine tolerance.
- Units. STL is defined in metres. Large models (in millimetres) are scaled ×0.001 automatically so they appear at real size.
- Geometry is preserved. Every triangle, with all object transforms applied, ends up in the new file.
IGES vs STL
| IGES | STL | |
|---|---|---|
| Full name | Initial Graphics Exchange Specification | Stereolithography |
| Stores | surfaces and curves | geometry only |
| Colour | No | No |
| Textures | No | No |
| Units | stored in the file | none – most programs read STL numbers as millimetres |
| Exact CAD geometry | Yes | No |
About the formats
IGES (Initial Graphics Exchange Specification) was published in 1980 by the US National Bureau of Standards. It is an older neutral CAD format that stores surfaces, curves and (sometimes) solids. It is still common in older CAD, CAM and tooling workflows.
STL (Stereolithography) was created by 3D Systems in 1987 for its stereolithography printers. It describes only the surface of a model as a list of triangles, without colour, materials or units. It is the default file for 3D printing and the format almost every slicer (Cura, PrusaSlicer, Bambu Studio, Chitubox) opens.
Frequently asked questions
Is this converter free?
Yes. You can convert IGES to STL for free – up to 3 conversions a day, with no sign-up and no watermark. If you need more, Pro gives you unlimited conversions and batch conversion (free for 7 days).
Are my files uploaded to a server?
No. The conversion runs entirely in your browser using WebAssembly and JavaScript. Your model never leaves your computer, which also makes it safe for confidential parts and patient data.
Is there a file size limit?
There is no fixed limit. Files of a few hundred megabytes work on a typical laptop; the practical limit is your device's memory.