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SD Card Guide

SD (Secure Digital) cards are convenient, low-maintenance memory storage for use in a broad spectrum of devices. SD comprises several families of cards: Standard-Capacity (original model), High-Capacity (SDHC), and Extended-Capacity (SDXC). This guide will lead you through the different types of SD cards to help you choose which card is best for you.

Capacity

SD cards are capable of storing up to 2GB. SDHC cards are capable of storing up to 32GB. SDXC are capable of holding up to 2TB. Some older devices may not be able to read/write to SDHC or SDXC cards.

Note: Some devices may recommend particular SD memory card types for optimal device performance.

Card Type	Logo	Capacity
SD		2GB and Below
SDHC		2GB To 32GB
SDHC UHS-I		4GB To 32GB
SDXC		32GB To 2TB
SDXC UHS-I		32GB To 2TB

Compatibility

Newer SD host products are capable of backwards compatibility. SDXC host products are able to run SDXC, SDHC, and SD memory cards. SDHC host products are able to run SDHC and SD memory cards. SD host products are able to run only SD memory cards.

Speed

It's important to choose the right Speed Class for your device. Speed Class Rating is a measurement of a card's minimum transfer speed* (this speed is standardized by the SD Card Association). The higher the speed class of a card, the faster the card's minimum transfer speed.

Note: In devices that require a constant stream of information to be written, such as video recording, the device might not perform at a satisfactory level if the class rating of the SD card is below a particular speed. For example, a camcorder built for a Class 6 card may suffer corrupted video if a Class 4 card is used. Digital cameras may experience a noticeable lag between shots, while the camera writes the picture to a lower class card. Check your device manual to find out the best Speed Class for your device.

Speed Class*	Logo	Transfer Speed	Recommended Uses
Class 0	N/A	Legacy (No Speed Rating)	Backing up, transferring and storing photos, music and other files
Class 2		2MB/s	File storage, still photography, standard video recording
Class 4		4MB/s	File storage, video recording, some full HD video recording, still photography, and some burst mode photography
Class 6		up to 12.5MB/s	Still photograhy, full HD video recording, burst mode photography
Class 10		up to 25MB/s	Still photography, full HD video recording, burst mode photography
UHS-I		up to 104MB/s	Recording real-time broadcasts, large-size HD video recording, burst mode photography

*Speed Class only identifies the minimum transfer speed of a card. Within the same Speed Class there can be higher or lower performing cards. For example, out of two Class 10 SDHC cards one may have a write speed of 14MB/s and the other with 18MB/s.