# Size of STL/OBJ files - too many triangles

**URL:** <https://discourse.slicer.org/t/size-of-stl-obj-files-too-many-triangles/5137>\
**Category:** Support\
**Tags:** segmentation, faq\
**Created:** [December 18, 2018, 10:58pm UTC](https://discourse.slicer.org/t/size-of-stl-obj-files-too-many-triangles/5137 "2018-12-18T22:58:43Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![cpinter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/cpinter/32/7995_2.png) [@cpinter](https://discourse.slicer.org/u/cpinter)\
**Post date:** [December 18, 2018, 11:33pm UTC](https://discourse.slicer.org/t/size-of-stl-obj-files-too-many-triangles/5137/2 "2018-12-18T23:33:06Z")

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There are two ways:

- Changes segmentation conversion parameter to enable decimation: Go to Segmentations module, long-click the Create button for Closed surface, select Advanced create or Update (depending on whether you had surfaces already or not). In the popup window choose the only path, and set a non-zero Decimation factor. 0.8 means that 80% of the triangles will be removed. Then export segmentation to STL
- Export segmentation to Model node (in Segmentations module bottom section or in Data module by right-clicking the segmentation). Then go to the Surface Toolbox module and do decimation on the model.

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_[View the full topic](https://discourse.slicer.org/t/size-of-stl-obj-files-too-many-triangles/5137)._