SD cards also come in a range of speed variants. This is often displayed on the card itself as a class rating in a small circle, ranging from Class 2 to Class 10.
| CLASS | BEST USED FOR | MINIMUM WRITE SPEED |
|---|---|---|
| Class 2 | Standard-definition video recording, general stills photography in compact cameras | 2MBps |
| Class 4 | HD video recording, continuous stills photography in compact cameras | 4MBps |
| Class 6 | Full 1080p video recording, continuous and regular stills photography in high-end compacts or ILCs | 6MBps |
| Class 10 | Full 1080p video recording, professional camcorder or continuous high-resolution stills in SLRs | 10MBps |
