> For the complete documentation index, see [llms.txt](https://docs.enercalc.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.enercalc.com/sel-faq/using-the-software/general-operation/supported-units-systems.md).

# Supported Units Systems

Supported unit systems in ENERCALC SEL

ENERCALC SEL generally only supports US Customary units.  The only exception at this time is the ENERCALC 3D module, which also offers support for SI units.


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