Compact storage solutions are now essential for our tech. Mobile phone, tablet or digital camera: almost every device takes SD cards. As the amount of data people use every day increases, memory cards have become increasingly smaller and cheaper to cope with the demand for storage.
MicroSD (Micro Secure Digital) cards are only the size of a fingernail, but they offer enough memory for plenty of photos, videos, music and documents. MicroSD cards are available in different memory sizes as well as speed classes. The cards available and what the specifications mean can be found here in our guide.
Origins of the MicroSD card
As with the first SD cards, MicroSD cards were originally developed by SanDisk, a manufacturer of memory solutions (previously called TransFlash). In 2005, SD Card Association, a global organization that sets standards for memory cards, announced its approval of the MicroSD.
A MicroSD card measures just 11mm × 15.0mm. Due to its small size, the card format is particularly suitable for small tech devices, such as smartphones or tablets, as a memory extension. For example, the SanDisk Ultra® MicroSDHC ™ 16GB and SanDisk Ultra® MicroSDHC ™ 32GB are ideal for storing all your photos and videos. The number on the label indicates the memory size of the card. In this example, 16GB or 32GB. MicroSD cards can also be used in digital cameras, navigation systems, mp3 players, and SD card slots using a suitable adapter. All MicroSD cards presented in this guide are supplied with adapters.
What types of MicroSD card are there?
On the market, there are three types of MicroSD cards that differ in terms of their file systems and memory size.
MicroSD cards have a capacity of 2 GB. They are formatted with the FAT16 file system.
MicroSDHC cards (Secure Digital High Capacity) have a capacity of between 4 GB-32 GB and are formatted with the FAT32 file system.
MicroSDXC (Secure Digital Extended Capacity) cards offer a capacity of between 48 GB-2 TB. They are formatted with the exFAT system. This category includes the SanDisk Ultra® microSDXC ™ Ultra 64GB and SanDisk® Ultra ™ microSDXC ™ 128GB. With such a high storage volume, a high-quality photo or full HD video can be recorded and stored one after the other.
Overview of speed classes
MicroSD cards are available in various speed classes. They are divided into Speed Class 2, 4, 6 and 10. The higher the number, the faster the data transfer. The value corresponds to the minimum transmission rate of the data in MB per second (MB/s). According to this, a Class 4 card transmits data with at least 4 MB/s.
The standard UHS Speed Class (Ultra High Speed) is available for SDHC and SDXC cards. UHS-I is capable of transferring data at a minimum speed of 10 MB/s, while UHS-II has a write speed of at least 30 MB/s.
Both memory card and terminal must support the specification.
The SanDisk® Extreme PRO® MicroSDHC ™ 32GB UHS-I is the perfect companion for anyone who wants to capture Full HD and 4K Ultra HD video and enjoy high-speed transfer rates. The SanDisk® Extreme PRO® MicroSDHC ™ 128GB UHS-I offers even more storage space. In addition to the Speed Class and UHS Speed Class, the Video Speed Class is another indicator of speed. The Video Speed Class includes the V6, V10, V30, V60 and V90. Memory cards like the SanDisk® Extreme® MicroSDHC ™ are ideal for recording 360° and virtual reality video with a Video Speed Class 30.
Speed rating
Sometimes a speed rating is found on the a MicroSD card, which provides information about the maximum reading speed. This value tells you how many times faster the MicroSD card works compared to the CD drive. The number is combined with the factor x, that is, the simple reading speed of a CD drive (150 KB/s). A factor of 1800x corresponds to a reading speed of approximately 270 MB/s.
Tips for purchasing a MicroSD card
Before you use a MicroSD card, you should always check which card types are compatible with your device, as not every device supports all capacities and formats. To avoid a defect, please read the operating instructions.
You should also consider the purpose for which the card is needed. C10, U1 or V10 are ideal for cameras. If you want to shoot full HD and 4K videos, U3 or V30 are a good choice. A UHS (Ultra High Speed) card should be taken if the terminal also supports this specification.
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