There are four standards for capacity:

	SD standard – Up to 2GB SD memory card using FAT 12 and 16 file systems
	SDHC standard – over 2GB-32GB SDHC memory card using FAT32 file system
	SDXC standard – over 32GB-2TB SDXC memory card using exFAT file system
	SDUC standard – over 2TB-128TB SDUC memory card using exFAT file system

		SD Standard	SDHC Standard	SDXC Standard	SDUC Standard
Capacity		up to 2GB	more than 2GBup to 32GB	more than 32GBup to 2TB	more than 2TBup to 128TB
File System		FAT 12, 16	FAT 32	exFAT	exFAT
SD Logo
Form Factor Size	SD	32 x 24 x 2.1 mm
	microSD	11 x 15 x 1.0 mm
Speed Classes	Normal Speed mode	C2, C4, C6
	High Speed mode	C2, C4, C6, C10,V6, V10
	UHS-I mode	—	C2, C4, C6, C10U1, U3V6, V10, V30
	UHS-II & III mode	—	C4, C6, C10U1, U3V6, V10, V30, V60, V90
	SD Express mode	—		E150, E300, E450, E600