A clean GUI tool that use Valve's BSPZIP command line utility. It is used to embed a folder with custom files (materials, models, sound,..) into a BSP file.

You can also repack a map to compress (or decompress it).

It can be used for any Source Engine game that provide a bspzip.exe.

This tool idea is based on Geotavros's BspZipGui .

2026 update: The tool is fully compatible with BSPZIP++ by ficool2.
Download BSPZIP++ here : HammerPlusPlus Tools

BspZipGUI v4.0

Select a game you defined (3 are setup per default), a custom folder you defined and load a BSP.

Check 'Use Directory Whitelist' (recommended) to only pack files from whitelisted directories (see Settings).

Press Pack Bsp.

Select a game you defined (3 are setup per default), a 'multi custom' folder you defined and load a BSP.

A multi custom folder contains one or more custom folder. The content of all those folders will be packed into the map

Check 'Use Directory Whitelist' (recommended) to only pack files from whitelisted directories (see Settings).

Press Pack Bsp.

Select a game you defined (3 are setup per default) and load a BSP.

Press Compress Bsp or Decompress Bsp.

Select a game you defined (3 are setup per default) and load a BSP.

Either select a directory (drag drop possible) and click Extract to Directory, or click Extract to Zip.

All packed files will be extracted to the directory/zip file.

Select a game you defined (3 are setup per default) and load a BSP.

Either select a directory (drag drop possible) and click Extract cubemaps, or click Delete cubemaps.

/!\ Deleting cubemaps actually delete every VTF files packed. That is how bspzip work.

Add new 'games' configs with the 'Add...' button. Delete them with the 'Delete' button.

Setup your games by loading the gameinfo.txt and bspzip.exe.

Add new 'custom folders' configs with the 'Add...' button. Delete them with the 'Delete' button.

Load the folder with the custom files that you want to embed in your map.

Add new 'multi custom folders' configs with the 'Add...' button. Delete them with the 'Delete' button.

Add the folders with the custom files that you want to embed in your map, with the "Add Directory" button.

Remove a folder from the list with Remove Selected.

Drag and dropping is supported.

Define a whitelist of subfolders and type of files (through their extensions) that can be packed.

(All the subfolders you would need are already setup, but you can edit to your needs)

To not bloat the UI, multiples settings can only be changed by modifying settings.xml.

When bspzip.exe is getting executed, you can either get the output of the process as it is getting executed (Async) or get all of it at once after it has finished (Sync).

It doesn't really affect the execution, but you can change it if you want by editing the following line:

• <IsSyncLogs>False</IsSyncLogs>

Meaning of the values :

• False means that logs are Asynchronously displayed, which is the default behavior
• True means that logs are Synchronously displayed
• Not having the line (if you had old settings), will use Asynchronous mode and next time settings are saved, the value will be at False.

With the release of BSPZIP++ at the start of 2026, it turned out this tool was not compatible directly with it.
Due to the usage of a relative path for the filesList.txt file used to list all the files to pack, it couldn't execute properly bspzipplusplus.exe, as an absolute path was required.
This issue is now fixed in the latest release.

BSPZIP++ also added new features, which werent in the default BSPZIP by Valve, so this tool programmed to be able to use them :

• -verbose parameter
• -threads N parameter for the Repack mode

I added extra parameters in the settings.xml file, which can only be edited directly in it (not with the tool). Those new parameters will let you use the new features of BSPZIP++

The parameters are the following :

• <UseBspZipPlusPlusArguments>False</UseBspZipPlusPlusArguments>
• <UseVerboseForPack>False</UseVerboseForPack>
• <UseVerboseForRepack>False</UseVerboseForRepack>
• <UseVerboseForExract>False</UseVerboseForExract>
• <UseVerboseForCubemaps>False</UseVerboseForCubemaps>
• <ExtraParametersPack></ExtraParametersPack>
• <ExtraParametersRepack>-threads 1</ExtraParametersRepack>
• <ExtraParametersExtract></ExtraParametersExtract>
• <ExtraParametersCubemaps></ExtraParametersCubemaps>

The setting UseBspZipPlusPlusArguments when equals to True will make the execution of BSPZIP/BSPZIP++ also use the others parameters associated to the current mode.
If you are not using BSPZIP++, make sure to keep it at False, because the default bspzip.exe will not like any extra unknown parameter and it will not execute correctly.

• If the mode is PACK :
  • If the setting UseVerboseForPack is equals to True, then the -verbose parameter will be added at the start of the command
  • The value of the setting ExtraParametersPack will be appended at the end of the command as an extra parameter
    • If the setting is empty, then just an empty string will be appended, which doesn't affect anything
• If the mode is REPACK :
  • If the setting UseVerboseForPack is equals to True, then the -verbose parameter will be added at the start of the command
  • The value of the setting ExtraParametersPack will be appended at the end of the command as an extra parameter
    • If the setting is empty, then just an empty string will be appended, which doesn't affect anything
    • This is the setting where you would add -threads N, for example -threads 2
• If the mode is EXTRACT :
  • If the setting UseVerboseForPack is equals to True, then the -verbose parameter will be added at the start of the command
  • The value of the setting ExtraParametersPack will be appended at the end of the command as an extra parameter
    • If the setting is empty, then just an empty string will be appended, which doesn't affect anything
• If the mode is CUBEMAPS :
  • If the setting UseVerboseForPack is equals to True, then the -verbose parameter will be added at the start of the command
  • The value of the setting ExtraParametersPack will be appended at the end of the command as an extra parameter
    • If the setting is empty, then just an empty string will be appended, which doesn't affect anything

Do note that the extra parameters are only important for the REPACK mode since it's the only one that really has a new parameter (-threads N).
But I added the settings for all modes because why not.
That will make this tool still compatible with any future new parameters that could get added to BSPZIP++

Windows has a hardcoded limitation for file paths, which affect bspzip.exe.

• Microsoft Doc

If a file path is 260 or more characters, and is packed by bspzip.exe, it will cause issues with packing the rest of the files. Because it's not something fixable with this software, I instead added a warning if such case happens.

The solution is simple and just requires you to have your custom folder in a shorter path.

• Moltard