bspconv

Quake bsp map converter tool The release is a pure .NET Framework 4.6 executable file, so it should work on other operating systems other than windows if you have a .NET runtime

Currently only Quake 3 (IBSP 46) and Quake Live (IBSP 47) maps are supported. Feature requests welcome. If you encounter any problems, please open a new issue here.

Quake 3 to Quake Live example

https://lvlworld.com/download/id:2527

Quake Live to Quake 3 example

bloodrun.bsp

bspconv.exe 46 pak00.pk3 --bsp:bloodrun.bsp