What Are the Classes of Micro SD Cards?

By Julius Vandersteen

MicroSD cards are small, inexpensive memory units that people use for storing data in MP3 players, cameras and other devices, and for transferring files between devices and a computer. They are rated in classes signifying their minimum sustained writing speed. MicroSD cards with faster writing speeds are especially useful when working with large files such as high-resolution videos. The SD stands for “Secure Digital.”

Class 2

Class 2 microSD cards have a sustained writing speed of 2 MB per second. These work with a normal bus and are suitable for activities such as SD video recording.

Class 4

Class 4 microSD cards have a sustained writing speed of 4 MB per second. These work with a normal bus and are suitable for tasks such as full HD video recording.

Class 6

Class 6 microSD cards have a sustained writing speed of 6 MB per second. These work with a normal bus and are suitable for activities such as full HD video recording.

Class 10

Class 10 microSD cards have a sustained writing speed of 10 MB per second. These work with a high speed bus and are used for tasks such as full HD video recording and HD still consecutive recording.

References & Resources