# STL dimension Bug - macOS Beta Version 3.56.1 (665)

**URL:** <https://discourse.shapr3d.com/t/stl-dimension-bug-macos-beta-version-3-56-1-665/10665>\
**Category:** Modeling Questions\
**Created:** [January 3, 2021, 5:56am UTC](https://discourse.shapr3d.com/t/stl-dimension-bug-macos-beta-version-3-56-1-665/10665 "2021-01-03T05:56:36Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![droussel](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/droussel/32/8714_2.png) [@droussel](https://discourse.shapr3d.com/u/droussel)\
**Post date:** [January 3, 2021, 5:56am UTC](https://discourse.shapr3d.com/t/stl-dimension-bug-macos-beta-version-3-56-1-665/10665/1 "2021-01-03T05:56:36Z")

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Hi,

- Change unit of measure to cm
- Create a 5cm cube
- Export to STL
- The result is a 5mm cube

I validated the resulting file in both Xcode and Prusa Slicer and validated against the same cube made in Fusion360.

You can see a video demo of the issue here: [iCloud](https://www.icloud.com/iclouddrive/0PiV9LpewAkGlyhB5bpwioPFw#dimension_bug_shapr)

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**Author:** ![Istvan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/istvan/32/23668_2.png) [@Istvan](https://discourse.shapr3d.com/u/Istvan)\
**Post date:** [January 3, 2021, 6:46am UTC](https://discourse.shapr3d.com/t/stl-dimension-bug-macos-beta-version-3-56-1-665/10665/2 "2021-01-03T06:46:53Z")

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Hi, it’s not a bug, STL does not contain unit information, so the actual size of the object will depend on how you export it: [https://support.shapr3d.com/hc/en-us/articles/115001796029-Why-did-my-STL-file-change-units-](https://support.shapr3d.com/hc/en-us/articles/115001796029-Why-did-my-STL-file-change-units-)

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<div class="post-metadata">

**Author:** ![droussel](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/droussel/32/8714_2.png) [@droussel](https://discourse.shapr3d.com/u/droussel)\
**Post date:** [January 3, 2021, 3:43pm UTC](https://discourse.shapr3d.com/t/stl-dimension-bug-macos-beta-version-3-56-1-665/10665/3 "2021-01-03T15:43:42Z")

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Oh wow, ok, I wasn’t aware of this! Sorry for the noise then.