Ultimate Memory Card Buying Guide and Best Cards for Cameras

Memory cards are essential to every photographer’s gear because they allow you to save all the photos and videos you have recorded in a safe place. There are a variety of different memory cards available on the market to cater to the cameras that utilize different memory cards. You will most likely need a particular memory card, depending on your camera. 

Memory cards are usually small in shape and provide a large amount of storage, which is perhaps its biggest advantage. They are reliable devices with no moving parts, meaning you can use them without any fear of destroying or damaging them. Due to their size, they are also highly portable. With the sheer amount of cards available on the market, it is essential that you do your research before deciding on one. 

SD Card Labeling and Specifications

SD cards and microSD cards on a table.

Of the many different kinds of memory cards available, SD cards are perhaps the most common type. If you have ever purchased an SD card, you may have noticed that a lot of information is provided to help you distinguish it from your other cards. It is crucial that you know what it is saying so that you can use it as it is intended. 

Other than SD, SDHC, or SDXC, you will also find a lot of different symbols, letters, and numbers. The numbers usually refer to the card’s minimum-rated sustained write speed. This number is usually either 4,6, or 10. A card rated class 4,6 or 10 will likely never write slower than 4,6 or 10MB/s, respectively. 

There is also a number 1 or 3 written alongside the letter U. So, U1 or U3 refers to the speed-class rating. U1 is identical to class 10, meaning that card is certified to write a minimum of 10MB/s. U3 cards mean that the card is certified to write 30MB/s or faster. The main difference between U1 and class 10 is that U1 and U3 are designed to indicate that they use the UHS-I or UHS-II bus. 

SD cards that do not have U1 or U3 ratings usually max out at speeds of 25MB/s, whereas if you own a UHS-I card, it will max out at 104MB/s. UHS-II cards are designed to have a second row of pins at the back of the card that helps it achieve speeds of up to 312 MB/s.

Most often, you will see the maximum achievable speed shown on the front of the card. This speed indicates how well a card may perform during bursts. In terms of reliability, it is better to focus on sustainable speed.

Memory Card Types

Multiple SD cards alongside other devices on a table.

With all the different memory card types available on the market, it can be challenging to choose one. Depending on your camera model, you may need to purchase a certain kind of memory card. However, each has its own purpose, advantages, and disadvantages.

Some of the most popular memory card types are SD / SDXC / SDHC, microSD, XQD, CFExpress Types A and B, Compact Flash, and CFast. 


SD in SD cards stands for Secure Digital. This memory card format was developed by the SD Association. Depending on the memory capacity you want, SD cards come in three different types, namely SD, SDXC, and SDHC.

These cards are the most common types used in cameras, which means your camera will most likely accept one of the three kinds of SD cards available. These memory cards are cheap, small, and relatively fast. Due to their small size, manufacturers can also implement dual slots in even the most compact devices. Here are the capacities of the SD card types.

Type Capacity
SD  2GB and under
SDHC Between 2GB and 32GB
SDXC Between 32GB and 2TB


A microSD card is a smaller version of a standard SD card. These memory cards are even smaller than SD cards, due to which they are often used in smartphones and tablets. You have to deal with some tradeoffs due to its size. For example, they are much slower, but they can still manage to store a large amount of data. 

These cards are incredibly versatile and are often available with an SD adaptor, meaning you can use them even in devices that support SD cards. They are most commonly used in phones, gaming devices, and even camera storage systems. microSD cards come in varieties depending on their storage, just like standard SD cards. These include microSD, microSDHC, and microSDXC.

Type Capacity
microSD  2GB and under
microSDHC Between 2GB and 32GB
microSDXC Between 32GB and 2TB


XQD memory cards were developed by Sony and are a much more reliable, faster, and higher-capacity alternative to SD cards. These memory cards are much thicker and more robust than other kinds of cards physically. They have been used in professional film and YouTube video-making applications. It is pretty common to find XQD card slots in camcorders and mirrorless cameras. 

These cards are often used due to their quick read/write speeds, which makes them incredibly useful for high-speed continuous shots. 

CFExpress Types A and B

CFExpress Type A and B cards are designed to have higher read and write speeds while using the same technology standards widely used in computing technology. CFExpress type A and B cards are fundamentally the same kinds of cards. Still, they are physically different, meaning there are differences in compatibility. If you place the two cards side by side, you will notice that CFExpress Type A is much smaller than Type B. This is because the two have a different number of PCle data transfer lanes. 

In CFExpress Type A, there is only one, while CFExpress Type B cards have two. There is another CFExpress Type C, but they aren’t usually used in cameras. CFExpress Type B cards are almost identical to XQD memory cards, which means you can use them in any camera that uses XQD. To do so, it is also vital that the manufacturer has released firmware that ensures compatibility with that kind of memory card. 

In terms of functionality, CFExpress Type B and XQD are pretty similar as both are limited by the transfer speeds of the devices. One advantage that CFExpress Type B cards have is that they have greater speed potential. 

CFExpress Type A cards are not far off from type B. They are a little slower and resemble SD cards. This means that you can insert a CFExpress Type A card in an SD card slot. This makes these memory cards extremely flexible. 

Compact Flash

Compact flash is an older card format still used in professional-level DSLR cameras. These memory cards are preferred in the photography industry because of how reliable and physically robust they feel. In terms of practice, they are not much different from SD cards.

These cards use UDMA labels, which help signify the card’s speed. UDMA 7 is quicker than UDMA 6. 


CFast memory cards are considered an upgrade of the Compact Flash memory cards, but the two cards are not interchangeable. Therefore, you must double-check the kind of card your slot is designed for before you purchase a memory card. CFast memory cards are designed primarily for video and broadcasting use. 

Things To Consider When Buying a Memory Card

A memory card and camera on top of a laptop.

When purchasing a memory card, you may become overwhelmed by all the choices available. Since cameras have been around for a long time, memory cards have also been refined, and many different kinds are available on the market. If you are confused about which memory card to purchase, you must look at specific features. They will help you narrow down your choices to select one that is perfect for you and your intended use.

Speed and Transfer Rates

Data read/write speed might not matter much when all you want is a memory card to store some photos. But you need a high-speed memory card for things like recording 4K videos and transferring large files to a PC/Mac. Both SDHC and SDXC formats support UHS (Ultra High Speed) interface, which comes in three versions i.e. UHS-1 (max speed 104MBps), UHS-II (max speed 312 MBps) and UHS-III (max speed 624 MBps).

However, your hardware should also support the UHS versions in order to achieve the maximum speeds. The good news is that UHS cards are backwards compatible and although they’ll work in compatible mode, the bus speed will reduce significantly. The default bus speed of all card types is 12.5BMps, while high-speed cards can achieve up to 624MBps (full duplex).

The actual speed depends on many factors, including the type of files being copied, the hardware and even the cables being used.

Identifying memory card speed isn’t so straightforward as there are many ways manufacturers use to define card speed. Some memory card manufacturers even use all those labels (which can make things more complex). 

Speed Class is a very important factor to consider, especially if you plan on using the memory card for recording videos (you need a certain constant speed when recording to avoid dropped frames). Speed Class shows the memory card write speed (minimum) in megabytes per second.

2 means at least 2MBps and so on, but you still don’t know what’s the maximum speed. A Class 4 card can still technically be faster than a Class 6 card (as you don’t know the maximum speed). Class 10 cards are the best bet if you want fast write speeds, which usually hover around 25MBps.

Some manufacturers mention Rated Speed, which shows the maximum speed in megabytes per second. This helps you choose the fastest memory cards without getting involved with too much technical details. However, the Rated Speed usually represents the speed in best cast scenarios or ideal lab conditions, not real-world performance.

Relative speed is essentially just a benchmark against the CD transfer speed, which was 150 KBps back in the old days. The relative speed (possible in ideal conditions) number shows how much faster a memory card is compared to the CD transfer speed. For example, 200X on a card means 200x150KBps = 15MBps.

The Video Speed Class is a relatively new class that represents the speed for various video formats. V90/60 is suitable for 8K videos, V60/30 for 4K video and so on. The minimum VSC write speed is V6 6MBps, V10 10MBps, V30 30MBps, V60 60MBps and V90 90MBps.

The UHS speed class shows the minimum write speed of UHS supported memory cards. U1 means a minimum write speed of 10MBps, while U3 means at least 30MBps write speed.

APC is representing the minimum level of performance when running/storing apps on an Android powered device. A1 means 1500 IOPS (Input Output Operations per Second) and 500 IOPS random write speed. A2 equals 4000IOPS and 2000 IOPS random write speed. Both A1/A2 promise a minimum 10MBps sustained sequential write. For cameras, APC is not that important as other speed indicators mentioned above as it just indicates application performance on Android devices.

CPRM (Content Protection for Recordable Media) supported memory cards provide protection against illegal copying. You might want to consider this feature if you are dealing with sensitive media, but not all manufacturers clearly mention CPRM on their memory cards (only mandated in Japan).

Memory cards don’t have an infinite operating life. The write/erase cycles represent the number of times a memory card can be overwritten before it starts to wear out (and finally fails). Most branded cards support up to 10,000 cycles so there is not much to worry about in this regard.

Storage Capacity

The storage capacity is often the deciding factor when buying a memory card for cameras and largely depends on your own requirements. It’s recommended to go for some extra storage space than what you think you might need.


Although microSD cards are compatible with most devices such as smartphones, cameras and tablets, they come in different varieties (a microSD card and a card with adapter for larger slots is the same thing).

Refer to the user manual of your camera/other device and note the type of microSD card it supports. What makes things confusing is that despite similar names, the four formats of SD cards might not be compatible with all hardware (SDXC supported devices are backward compatible with SDHC and microSD cards). 


When purchasing a memory card, you must focus on its durability. Although SD cards and other memory cards usually have no moving parts, they are more durable than other camera accessories. These cards rely on an electronic chip, which stores their data. 

These cards do not require power but can still be damaged by fire, water, and physical pressure. Due to this, the outer layer of your memory card must be sturdy. Some companies offer tough bespoke versions of their memory cards, which are highly durable. They are designed to withstand all the elements and can even survive extreme temperatures. So, if you plan a photography adventure in places with rough terrains or extreme temperatures, you should purchase these memory cards. 


When purchasing memory cards, capacity is vital. Due to the advancement of technology, even the smallest of memory cards can hold gigabytes and even terabytes of storage. Depending on your use, you may need one that is only 8 to 32GB, or you may require one that has 1 TB of storage. If you use your device to take videos, you should ideally purchase a memory card that has a large capacity. The one downside to buying large memory cards is that you will lose a lot of data if they get lost or corrupted.

Professionals suggest it is much better to have multiple smaller-capacity memory cards instead of one with a large capacity. Although that may be expensive, you will end up saving yourself the pain of losing all your data in case a card gets lost or corrupted.

It is also essential that you check the size of the memory card your device can handle. Some devices limit the capacity of the cards they can expect. You should also note that cards that have a larger capacity are more expensive. 


As memory cards save the images you capture on your camera, you must purchase a reliable memory card. Since memory cards usually do not come with any moving parts, they are not as prone to breaking, but still, it is essential that you choose one from a well-known brand. Additionally, some memory cards also come with a lifetime or 10-year warranty, so it is best to purchase one that comes with one. 

Brand and Price

Different brands have different reputations for quality and reliability, you should research and compare brands before making a purchase. Price is also an important factor to consider, but keep in mind that you usually get what you pay for and that a higher price doesn’t always mean better quality or performance.

Pros and Cons of Memory Cards

Here are some pros and cons that are worth considering when deciding whether to use them as a storage solution.

Pros Cons
Memory cards are available in a wide range of capacities, from several gigabytes to over a terabyte.  Memory cards are relatively fragile. They can be easily damaged if they are dropped or bumped, or exposed  to water or extreme temperatures
Modern Memory cards support fast data transfer speeds, allowing you to quickly transfer files between devices.  Memory cards have a limited lifespan and can become unreliable over time, even with proper usage.
Memory cards are relatively inexpensive compared to other storage devices, making them an affordable option for storing files.


1. Does the speed of the card matter?

Yes. The faster the speed of your camera, the less it will buffer or lag. This means that when you are shooting videos or taking pictures, a faster memory card will save them much faster than a standard memory card. 

2. How many years does an SD card last?

If you own an SD card, it will most likely last you for at least 10 years or even more. If you use it very frequently, then you may need to change it out often, but most memory cards are designed to be durable. 

3. What causes memory cards to get damaged?

One of the common reasons why a memory card stops working is because it gets corrupted. There are many reasons this can happen, and some of them are improper use, manufacturing defects, physical damage, and malware. However, most SD cards can be fixed without needing to format them, so all your data will remain safe. 


Memory cards are essential that no photographer can go without. They are highly versatile and used in various devices such as smartphones. Due to their wide range of usage, a large variety is available on the internet. This makes it a little complicated when choosing which one to buy. 

If you are looking to purchase a memory card, it is vital that you take a few factors into consideration. These include the capacity, the transfer rates, the durability, and your budget. By taking these factors into account, you will be able to purchase a memory card that fits your needs and will serve you well over the years.