NSP vs XCI vs NSZ: which Switch ROM format should you download?
September 4, 2026
NSP
An installable package. It installs into internal or SD storage and appears on the home screen like any other title. This is the format most people want.
XCI
A cartridge image. It behaves like a physical game card rather than an installed title, which some emulators prefer.
NSZ
A compressed NSP. Smaller to download, but your installer must support the format before it will work.
Which to choose
On a console, NSP is the simplest. On an emulator, XCI often loads with the least configuration. If bandwidth matters and your installer supports it, NSZ saves considerable download size.