Scale UVs To Bounds
From Nevercenter 3D Modeling Wiki
Default Shortcut: None
Menu Path: UVs/Materials > Scale UVs To Bounds
Description
This command will scale the selected UVs so that they fit in the 0-1 UV grid, and position them within the grid.
Notes
- Arrange UVs In Bounds is similar, but it will also rearrange individual UV islands to ensure a better fit.