nx-title-id

Prints the title ID of the Nintendo Switch game whose packages (.nsp, .nsz, .xci, .xcz) are in a folder.

uvx nx-title-id <folder> [-k prod.keys]

Base games, updates and DLC in the same folder all count as their base game, so a folder with one game prints one line:

$ uvx nx-title-id ~/Games/Super\ Mario\ Odyssey
0100000000010000

How the title ID is found

For each package, in order:

1. The ticket's name. A package's ticket is named after its rights ID (<32 hex digits>.tik), whose first 16 digits are the title ID. This wins over the file name, since tags in file names can be wrong.
2. A [title ID] tag in the file name, such as Game [0100000000010000][v0].nsp.
3. The meta NCA. For a package with neither, the NCA headers are decrypted with header_key from prod.keys, and the lowest title ID among the meta NCAs is used. The keys file is -k, else ~/.switch/prod.keys when it exists; it is read only when a package needs it, and no key value is printed.

Steps 1 and 2 use only the Python standard library. Step 3 uses pycryptodome for AES.

Cartridge images (.xci, .xcz) seldom carry a ticket, so they usually need a tag or the keys. Cartridge dumps with the 0x1000-byte key area at the start, and NCA0 headers from very early titles, are not read.

Exit status

0 when at least one title ID was printed. Non-zero, with a message, when the path is not a folder, no package has a readable title ID, the keys file is missing or has no header_key. When the folder holds more than one game, every title ID is printed and a warning goes to stderr.

Development

uv run nx-title-id <folder>       # run from this folder
uv run tryke test                 # run the tests
uv build                          # sdist and wheel into dist/
uv publish                        # upload to PyPI