What is a .pak file?
Game Package / Archive File · Archive
A .pak file is a game data package: textures, models, sounds and scripts bundled into one archive so the engine loads them fast. Each engine defines its own PAK layout, so there is no single format.
What is a .pak file used for?
The name goes back to id Software's Quake, whose PAK archives started with the ASCII bytes PACK. Modern engines kept the extension but not the layout: Unreal Engine .pak files, for example, use their own structure with optional compression and encryption.
Many PAKs are ZIP archives in disguise (Quake 3's .pk3 openly so), which is why trying 7-Zip is the standard first move. Modding tools per game handle the rest; repacking wrongly can corrupt the game.
How to open a .pak file
The .pak format opens in the following apps, grouped by operating system. If one app does not work, try another from the same list. For a step-by-step walkthrough, see how to open a .pak file.
Windows
- 7-Zip (if ZIP-based)
- game-specific modding tools
- PakExplorer-style utilities
macOS
- The Unarchiver (if ZIP-based)
- game-specific tools
Linux
- 7-Zip / unzip (if ZIP-based)
- game-specific tools
How to convert a .pak file
You can convert a .pak file to zip (repack, engine-dependent) using a conversion tool or the export menu of an app that opens it.
.pak file signature (magic bytes)
Programs recognise a .pak file by the bytes at the start of the file, not by its name. These are the signatures for PAK.
| Hex signature | Offset | Note |
|---|---|---|
| (no fixed signature) | 0 | engine-specific; no single fixed signature (Quake-era PAKs start with ASCII PACK) |
See the full magic-numbers reference for every format.
Frequently asked questions
What is a .pak file?
A .pak file is a game data package: textures, models, sounds and scripts bundled into one archive so the engine loads them fast. Each engine defines its own PAK layout, so there is no single format.
How do I open a .pak file?
Try 7-Zip first, since many PAKs are ZIP-based. If that fails, the file uses the game engine's own layout and you need that game's modding or unpacking tool.
Can I delete .pak files to save space?
Not from an installed game: they are its assets, and the game will break or re-download them. Only delete PAKs belonging to mods you no longer use.
Why does my extracted .pak content look scrambled?
Some engines compress or encrypt their PAKs (modern Unreal games often do). Generic tools then show garbage; only a tool for that specific game can unpack them.
Related formats
Sources
Details on this page were checked against authoritative references: