The only way to add more storage to the Nintendo Switch is with a microSD card. However, not all SD cards are created equal, and using some types of cards could slow down your games.
Nintendo Switch and Switch Lite consoles have 32 GB of internal storage, with the OLED model bumping that up to 64 GB, but the operating system eats up some space on all models. That might only leave you enough room for a handful of games, which is why the Switch also has a slot for microSD cards up to 2 TB in size. Once you have a microSD card, you can download new games or game data directly to the SD card, or you can move data back and forth as needed between internal and SD storage.
Not All SD Cards Are Equal on the Switch Nintendo's SanDisk microSD Cards Are Slower, Too Switch Internal Storage vs. SD Card Benchmarks Ensure Your Switch Has a Speedy SD Card
The main problem with SD cards is performance — even the fastest SD and microSD cards have a fraction of the read and write speeds of other flash storage. For example, Samsung’s new line of Pro Plus microSD cards have read speeds of up to 180 MB/s and write speeds of up to 130 MB/s. That’s faster than most USB flash drives, but less than half the read and write speeds of a typical SATA internal SSD — the Samsung 870 EVO maxes out at around 560 MB/s. The NVMe storage used in newer PCs and game consoles blow that out of the water, often pushing 7,000 MB/s.
Since we’re dealing with such slow storage, every bit of performance matters, even if game performance is ultimately limited by the Nintendo Switch’s other hardware. You should ideally have the fastest microSD card possible, especially one with an A2 rating. The A2 badge means the card was designed for storing applications with decent
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