What is a .UCAS file?
UCAS holds the cooked asset data of an Unreal Engine game, paired with UTOC.
- Did you know
- UCAS is the container that actually stores a packed Unreal game’s assets.
- UCAS is part of Unreal Engine’s IoStore packaging, paired with a .utoc table of contents that records each asset’s id, offset and size.
- IoStore was introduced to speed up loading, replacing the older .pak archive approach with a content store designed for fast, ordered streaming.
- What Analyser reads
- Identify and read more game and emulator files: Unity asset bundles, Unreal cooked assets, CISO/CHD disc images, FMOD/Wwise sound banks, Spine skeletons and atlases, GameMaker/LDtk/TIC-80 projects, Minecraft Anvil regions, Warcraft III maps, Ren Py and RPG Maker data, extra console ROMs (Atari, PC Engine, Master System/Game Gear, WonderSwan, 3DS homebrew), xdelta/Basis patches and emulator saves and movies.
- Depth of analysis
- .UCAS is an identification-grade format: Analyser recognises it from its bytes and decodes the header metadata it carries, rather than opening it in a full viewer. Formats that do get a full viewer are marked "Full" on the formats page.
- Open a .UCAS file
- Drag a .UCAS file onto the Analyser home page (or tap to pick one). It is identified entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.