Skyrim Special Edition
0 of 0

File information

Last updated

Original upload

Created by


Uploaded by


Virus scan

Safe to use

About this mod

A tool that optimizes NIF files for the SE/AE (or LE) format and fixes several potential issues. Also scans textures for compatibility.

Permissions and credits
SSE NIF Optimizer
a tool to optimize Skyrim NIFs for SSE

This is a tool that optimizes NIF files for the SE/AE (or LE) format and fixes several potential issues.
Also scans textures for compatibility.

  • Make sure to create backups of your NIFs beforehand!
  • Don't run it on your entire meshes folder at once.
  • Use the head parts option on ONLY head parts, without exception!

So it's better to temporarily copy/paste all those heads, eyes, hairs to a separate folder for optimization.
Things like helmets are regular meshes, not head parts.

If a NIF is already in the SSE format, the tool optimizes them as well, but it doesn't perform as many cleanup operations.
Note that SSE-formatted NIF files do NOT work in the old Skyrim any longer.

To view the new NIF format in NifSkope, you will need the very latest version currently found here:
NifSkope releases by jonwd7

Please let me know if there are any problems with a NIF and if possible, provide the files before and after optimization.
If this tool helped you with your mod, it would be cool if you could give it credits, but that's not required of course. :)

For the source code, check SSE-NIF-Optimizer and nifly on GitHub (GPLv3 license).

What it does:
  • Optimizes NIFs to the new SSE format (BSTriShape, changes to NiSkinPartition).
  • Optimizes head parts to BSDynamicTriShape (separate checkbox).
  • Triangulates the geometry and skin partitions.
  • Cleans up the NiSkinData (source for vertex weights that are unused in-game).
  • Calculates new bounding spheres for geometry and all of the bones.
  • Adds tangents to all meshes that need them.
  • Removes normals and tangents from all meshes that don't need them, such as body meshes.
  • Removes all-white vertex colors from meshes.
  • Renames all meshes that have the same name, since they need to be unique.
  • Cleans up the header strings.
  • Deletes all blocks that aren't referenced somewhere within the root node tree.
  • All of this results in a hopefully working NIF that's cleaned up and smaller in file size.
  • Works on NIFs that already are in the SSE format as well.
  • Can revert the format to LE.
  • Scan textures for SSE compatibility.

Things to keep in mind:
  • SSE has a lower precision for UV coordinates, so if you happen to stumble upon a mesh that makes use of coordinates way outside of the 0.0 - 1.0 range, you should probably re-center the UVs using NifSkope before optimization.

This can't and doesn't need to be installed with a mod manager, as it is a utility for modders.
Simply download the archive, extract the executable and run it, then follow on-screen instructions.

There's no uninstallation process, simply delete the executable from your computer.

Running from the command line:
/opt SE "file.nif"
/opt SE "folder"
/opt SE /recursive "folder"
/opt SE /headparts "headpart.nif"
/opt LE /log "log.txt" "file.nif"

jonwd7 - For assistance with the format and general help.