Inexpensive and easy to find, the micro-SD card is the easiest way to add storage to a mobile device. To help you find your way around, we have made a small selection for you.
Launched in 2005 with a staggering 16 MB capacity, the good old microSD card has come a long way! Although its format has not changed, under the hood there are many developments, opening the door to ever higher speeds and capacities.
Sold at ever more attractive prices, microSDs are a good way to increase the storage space of a smartphone at a low price.
Be careful though: the performance of the latter is significantly worse than that of internal storage. It will therefore be better to store non-critical data such as photos or music there and keep internal storage for apps. We also have a short guide to moving apps and content from your Android smartphone to the microSD card.
In the jungle of formats
We therefore switched from SD format to SDHC in 2006 and then to SDXC in 2009. The latter represents the vast majority of cards on the market and provides, among other things, a maximum capacity of 2 TB and peak speeds of 300 MB / s. .
A new version of the standard was announced in 2018: the SDUC which brings the maximum capacity to 128 TB. In parallel, the SD Express 8.0 format has also been defined, which allows cards to use a PCI-Express 4.0 link and therefore achieve speeds of 3.9 Gb / s. Small peculiarity however: the SD Express, independent of the SDUC, can also be implemented on SDHC and SDXC cards. However, no commercial model is currently available.
Which card for which use?
All cards are not created equal, on the contrary. Two cards of the same capacity may have very different speeds and therefore will not meet the same needs. A fan of 4K video will favor a high writing speed while a Switch will especially benefit from a good reading speed.
To find your way around, we will use three types of certifications.
- The UHS speed class: it measures the sequential writing speed and is in the form of a U with a number in it. A U1 will therefore correspond to 10 MB / s and a U3 to 30 MB / s.
- The video speed class: it measures the sustained writing speed and is in the form of a V followed by a number describing the bit rate.
- Some cards have an application performance class label, designated as A1 or A2, which guarantees a certain number of IOPS as well as a sustained write rate of 10 MB / s.
If you plan to make video, choose at least a U3 or V30 compatible card. Faster cards exist, but they have limited compatibility due to the number of different pins. So make sure your device supports them.
For a Nintendo Switch, however, there is no need to break the bank: it only supports U1 cards. So putting in more money will not improve loading times.
Beware of counterfeits
Very popular, microSD cards are probably the most counterfeit high-tech product to date. Marketplaces are full of cards sold at unbeatable prices and featuring the graphic identity of better-known brands.
Buying them, however, will be a very bad calculation. The speeds are often poor, the capacities not respected and the cards tend to die quickly. For greater security, therefore, stay with established resellers and do not hesitate to return any product that appears suspect. A fuzzy print on the card or its packaging is a common clue.
If you are looking for a good external drive to copy data from your microSD card, head to our dedicated guide.
Sandisk Ultra: the SD card for everything
The new Ultra range from Sandisk is now a very good choice to increase the storage of a smartphone. Now compatible with the A1 standard, they allow you to quickly load applications installed on them and offer a reading speed of up to 100 MB / s. The range is very complete and offers storage capacities of 16, 32, 64, 128, 200, 256 GB, 400 and 512 GB for prices ranging from 6 to 135 euros.
This very versatile card will suit many devices, from your smartphone to your Switch to your camera. That being said, if you are looking above all for performance, especially to shoot in UHD at 60 frames per second, or to facilitate the transfers of many images from your SLR or to access them more quickly, it will be better to opt for more powerful cards. We advise you to use UHS-3 (U3) compatible cards (see below).
Depending on your use, we recommend that you choose the 64 GB, 128 GB or 200 GB references which offer the best quality / price ratio in the range and which will undoubtedly meet your needs.
Samsung EVO Plus: good value for money
If you are looking for more performance, while keeping a low price, we advise you to turn to Samsung and its Evo Plus range. These very good quality micro SD cards are UHS-3 (U3) certified. This certification allows them to achieve a write speed of up to 90MB / s, it will bring you more convenience for 4K videos.
As you can see, this range will appeal to video enthusiasts who are looking above all for additional storage space to record hours of rush in high definition. If it is especially in this area that you will benefit the most, you will also have a performance gain on Switch or smartphone.
Sandisk Extreme: Speed for everyone
The new Sandisk Extreme range has all the certifications one would expect from a micro SD card in 2018 UHS-3 and V30. In addition, it is one of the first consumer micro SD cards to be A2 certified, which guarantees it to process more operations per second for better performance for the applications stored on it.
They are less affordable than the references Ultra from Sandisk and EVO Plus from Samsung, but guarantee excellent performance and can be a worthwhile investment for those who use a micro SD card daily in a smartphone. You can do anything with it.
Sandisk Extreme Pro 64 GB: speed above all
If you’re looking for the fastest card possible, you’ll often have to sacrifice capacity, as 64GB cards are indeed the fastest. Among these, the Sandisk Extreme Pro catches our attention.
It reaches 275 MB / s in reading and offers some of the best IOPS performance on the market. To take full advantage of it, however, you will need a UHS-II compatible device and memory card reader.
Finally, the price is particularly high! A 64 GB card will cost you almost the same price as a slower 400 GB model… But if you need the fastest, look no further.
What about the readers?
The memory card reader is often a device that we forget and that’s a shame. The readers integrated into our PCs are indeed slow and will not be sufficient to fully exploit a fast card.
What to look out for before buying a micro SD card?
What storage capacity do I need?
Before buying a micro SD card to increase the capacity of your smartphone, tablet or game console, you must first know what storage capacity you expect. 16 and 32 GB is enough to store your music as well as a few videos, but if you want to store more movies, apps and games, you will need more storage capacity. Today, we recommend taking 64 GB or 128 GB as the “default” capacity.
SD, SDXC, SDHC… does that change anything?
Yes in theory… in practice not much. Basically, these terms refer to different storage capacities. The SD (SC) for “Standard Capacity” goes from 128 MB to 2 GB, the SDHC (High Capacity) up to 32 GB, the SDXC (eXtended Capacity “up to 2 TB. Have subsequently been added to ‘other things like bus speeds, which involve different connectors. In practice, nowadays almost all products support all standards. You just have to look into it if you want to add an SD card in an aging device, i.e. before 2010.
What are A1 and A2 certifications
The “A” certification is related to inputs / outputs per second (IOPS). They mostly make sense for smartphones and the Switch. The A1 certification corresponds to a minimum of 1500 read and 500 write IOPS, the A2 to 4000 and 2000 IOPS, respectively. The more there is, the better, because data will flow better between the terminal and storage.
What do SD card classes mean?
The “class” of a card ranges from 4 to 10 and is numbered “C” followed by a number. From class 10, we switch to so-called “high speed” or Ultra High Speed UHS abbreviated classes. All of this corresponds to minimum sequential write speeds. The C4 and C6 are now almost non-existent. It should therefore be remembered that the C10 corresponds to speeds of 10 MB / s minimum.
What is the UHS class?
Beyond class 10, we go to so-called UHS (Ultra High Speed) classes that are not subject only to sequential writing speeds. Transfer debits are also taken into account. UHS-I corresponds to 104 MB / s maximum, UHS-III to 624 MB / s. More recent, there is the SD “Express” which goes up to 985 MB / s. The latter is still relatively rare and does not exist. no compatible consumer device at this time. UHS-I will suffice for 4K at 30 fps, for 60 fps and more, prefer UHS-III.
There are also Video classes, displayed as “Vxx”, but they are actually a bit redundant with UHS classes. Remember that from video class 30 you can shoot 4K at 60 frames per second.