What is the XCI file format?
An .xci file is a binary image of a Nintendo Switch game cartridge, created by dumping the eMMC chip embedded in a physical cartridge. The format was introduced alongside the Nintendo Switch console launch in March 2017 and is sometimes called an NX Card Image or eXternal Cart Image.
The file structure begins with an encrypted Gamecard header in the first 0x200 bytes, followed by a cartridge certificate and card metadata. At offset 0x10000, an HFS0 (Hash FileSystem) partition table contains sub-partitions named secure, normal, update, and logo. Inside the secure partition, Nintendo Content Archive (.nca) files hold the actual game data - encrypted executables in ExeFS format and game assets in RomFS format.
All content is encrypted with AES-XTS using keys derived from device-specific master keys. To use an .xci file with an emulator, decryption keys (prod.keys) must be dumped from a physical Nintendo Switch console. Without these keys, the file cannot be decrypted or launched.
File sizes range from 512 MB to 32 GB, matching physical cartridge chip capacities. The format is distinct from .nsp (Nintendo Submission Package), used for digital eShop games. The compressed .xcz variant applies NCZ compression to reduce file size without altering the core structure.
Both major Switch emulators, Yuzu and Ryujinx, were shut down following Nintendo legal action in 2024. Community forks continue development but remain in legal uncertainty.
Security & safety
RISK: MEDIUMXCI files themselves are not malicious (encrypted game data). However, sites distributing XCI game dumps for games users do not own are piracy sources. Risk: downloading from unofficial sources may deliver malware embedded alongside or disguised as .xci files. The legal risk of possessing commercial game dumps without owning the cartridge is real (copyright infringement). The emulator ecosystem has also been targeted by Nintendo legal action (Yuzu shutdown 2024, Ryujinx settlement 2024). Use only legal, self-dumped cartridges; use Lockpick_RCM or Hekate-based tools on a physically owned console to dump keys/games legally.
Format details
in a nutshellFULL NAMENintendo Switch Cartridge Imageaka NX Card Image, Switch ROM dump
DEVELOPERNintendosince 2017 (Nintendo Switch launch, March 3, 2017)
CATEGORYGame Files
MIME TYPEapplication/octet-stream
TYPEProprietary encrypted game cartridge image (binary)
This extension is also used by…
- Adobe Reader Font Mapping File - Adobe Acrobat/Reader uses .xci for XML-based font mapping configuration files; entirely unrelated to Nintendo Switch. This is the db_name entry - see db_audit_notes.
- Xilinx Vivado IP Configuration File - Xilinx/AMD FPGA tools use .xci for IP core configuration; unrelated to both Nintendo and Adobe.
MAGIC BYTES · FILE SIGNATURE
OFFSET
00010203
HEX
48454144
ASCII
HEAD
The XCI file's first 0x200 bytes are an encrypted Gamecard header. The HFS0 (Hash FileSystem 0) partition table starts at offset 0x10000 and begins with the ASCII string "HFS0". The XCI format consists of header (0x200 bytes) + certificate (0x200 bytes) + card metadata + HFS0 partitions. Content is encrypted with AES-XTS using keys derived from console-specific master keys. Note: SwitchBrew documents the header starts with "HEAD" magic (bytes 48 45 41 44) at offset 0.
Programs that open XCI files
Windows3 apps
Ryujinx (community fork)
Open-source Add game folder containing .xci; requires prod.keys dumped from a physical Switch. Original Ryujinx shut down Oct 2024; use a community fork.
Suyu
Open-source Open .xci directly; requires console keys (prod.keys). A community continuation of the Yuzu emulator after its 2024 shutdown.
hactool (command-line)
Open-source Command-line tool to extract/inspect XCI contents (NCA partitions). Requires prod.keys. For developers/researchers, not casual users. 
macOS1 app
Ryujinx (community fork)
Open-source Available for macOS; requires prod.keys from a physical Switch console. 
Linux1 app
Technical details
deep spec| File type | Proprietary binary game cartridge image dump |
| MIME type | application/octet-stream |
| Byte order | little-endian |
| Container structure | HFS0 (Hash FileSystem 0) partitions: secure, normal, update, logo |
| Encryption | AES-XTS per-sector; keys derived from device-specific master keys |
| Decryption key file | prod.keys - must be dumped from physical Nintendo Switch hardware; required by emulators |
| Magic bytes | HEAD (48 45 41 44) at offset 0x0 (encrypted Gamecard header) |
| Header layout | 0x200-byte encrypted Gamecard header; 0x200-byte certificate; HFS0 root partition table at offset 0x10000 |
| Inner format | NCA (Nintendo Content Archive) files containing ExeFS (executable) and RomFS (game data) |
| Integrity checking | SHA-256 hashes stored in HFS0 partition headers per file entry |
| Typical file size | 512 MB - 32 GB (matches physical cartridge eMMC chip capacity) |
| Cartridge chip capacities | 1, 2, 4, 8, 16, or 32 GB eMMC |
| Compressed variant | .xcz - applies NCZ compression to individual NCA files within the XCI container |
| Padding | Files may contain blank padding if game data is smaller than the physical chip capacity |
| Released | 2017 (Nintendo Switch launch, March 3, 2017) |
| Latest version | current (no version number published; format tied to Switch hardware revision) |
| Specification | switchbrew.org |
XCI conversions
Community Q&A
asked by users
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Frequently asked questions
What is an .xci file?
A Nintendo Switch game cartridge image - a binary dump of the physical cartridge's storage. Encrypted with Nintendo's AES-XTS keys.
How do I open/run an .xci file?
You need a Nintendo Switch emulator (Ryujinx community fork or Suyu) and decryption keys (prod.keys) dumped from a physical Switch console. The original Yuzu and Ryujinx were shut down in 2024; community forks continue.
What is the difference between XCI and NSP?
XCI is a cartridge dump (physical game image); NSP is a digital/eShop game package. Both store the same NCA game files but in different container layouts. Most emulators accept both.
Is it legal to use XCI files?
Dumping a cartridge you own for personal backup may be legal in some jurisdictions. Downloading or distributing XCI files for games you don't own is copyright infringement. Nintendo has successfully sued emulator developers.
Why is my XCI file so large?
XCI is a 1:1 cartridge image including blank padding to fill the eMMC chip (1/2/4/8/16/32 GB). The actual game content may be smaller. .xcz is the compressed variant.
What happened to Yuzu and Ryujinx?
Yuzu was shut down in February 2024 following a Nintendo lawsuit and $2.4M settlement. Ryujinx was shut down in October 2024 after a separate agreement with Nintendo. Community forks continue.
References
1Adobe Experience Manager - Specify XCI configuration optionsexperienceleague.adobe.com
2SwitchBrew - XCI format documentationswitchbrew.org
