If you have ever looked closely at memory cards, then you have likely noticed various abbreviations and symbols on the memory cards. To the untrained eye, these symbols can be as meaningful and easy to read as ancient Egyptian hieroglyphs on the wall of a pyramid. However, to those that know what to look for, it can ensure they pick the right memory card with the right features for their specific use case.


Luckily, understanding SD cards isn’t as complicated as learning to read the ancient Egyptian hieroglyphs. With a little bit of practice, you can also understand various SD card label meanings and ensure you always have the right tool for the task at hand.


What do Memory Card Symbols Mean?


When looking at a memory card, there could potentially be a half dozen or more words and symbols jammed into the limited surface area of the memory card’s label. Understanding what everything means is important when selecting a memory card.



This is one of the most basic features of a memory card and probably one of the easiest symbols to understand. It outlines how much storage space is available on the memory card. This is measured in gigabytes, or “GB” for short. Some of the most common capacities available today are 16GB, 32GB, and 64GB. Higher capacity means more storage room for your photos, songs, videos, etc.



Memory card labels will also show the read and write speed of the card. This can be somewhat confusing as some brands will use a single number shown as megabytes per second or MB/s. Other brands may show different speeds for reading and writing. Some brands may denote speed as a factor with an “x” suffix, like 600x, for example. You will want higher speeds for more advanced cameras where you may be shooting video or burst images.


Type of Card

One of the most important symbols to understand is the card type. Many people are familiar with SD cards, which is a common type of card that has been available for some time. However, there are now SDHC and SDXC cards available now too. The newer types denote that the card has a higher capacity. SDHC cards have capacities from 4GB to 16GB, while SDXC cards can store 64GB and higher. New devices are backwards compatible and can support the older SD format. However, an older device will not be able to support SDXC, for example.


Speed Class

The speed class symbol is different from the speed mentioned above. You are probably beginning to see why understanding these cards can be somewhat complex. The speed class is shown as a symbol with a number surrounded by a “C.” The speed class helps buyers understand the minimum sustained write speed. The higher the number, the higher sustained write speed the card is capable of. Those taking full HD video will want a higher speed class card than someone who is simply taking intermittent photos.


UHS Speed Class

UHS speed class is used on the newer SDHC and SDXC cards. This is shown with a symbol that looks like either a 1 or a 3 inside of a “U.” Like the other speed class symbol, this tells the user the minimum write speed of the card. UHS speed class 1 has a minimum speed of 10MB/s while UHS speed class 3 has a minimum write speed of 30MB/s.


Video Speed Class

Getting sick of the different speed classes? There’s one more to understand. Some cards that are designed for video use will have a video speed class symbol that looks like a “V” with a number next to it. The number represents the minimum write speed in MB/s. You may find symbols that read V6 all the way up to V90. V10 and V30 are commonly used for 1080p, V60 is used for 4K, and V90 is used for the much less common 8K video.


The Extras

As if all of that wasn’t enough, there may be some other words or symbols you may find on memory cards. Of course, manufacturers will often put on the brand name and model name of the card. This should be relatively easy to figure out, especially if the memory card is still in its packaging.


Other types of cards, like CompactFlash cards, have their own symbols and designations but are generally much more straightforward to understand than the SD family of memory cards. UDMA is commonly used on CompactFlash cards and denotes the write speed of the card. If your device uses one of these cards, consider yourself lucky as they are much easier than understanding SD cards.


How to Understand SD Card Label Meaning


There may be a lot of symbols, words, and numbers on your card. Generally speaking, they are all trying to help you understand the performance of the card so that you can ensure it meets the needs of the device you’re using. So, how do you make sense of it all?


The easiest way to understand what SD card symbols you need to look for is to consult the manual for the device you’re using. In the manual, it will outline the minimum basic requirements to get the best performance. This will help you understand more clearly which SD card to look for.

Find the Right Card Today


Understanding SD cards can feel daunting, but you should be well on your way to becoming a professional SD card translator. If you’re still unsure about SD card label meanings, be sure to reach out to the experts at Advantage Imaging Supply for help with choosing the right SD card for your device.