To extend the storage capacity of a Nintendo Switch, GoPro, or Raspberry Pi, one typically requires a microSD card. However, while many cards are speedy enough for file storage, certain low-cost options perform better than others. Benchmark tests have been conducted to assist you in finding the optimum microSD cards for your storage needs.
When shopping for a microSD card, the first consideration should be the required amount of space. Typically, modern cards range between 32GB and 512GB, with a few models offering 1TB. However, while 2TB cards are theoretically plausible, they are still at the prototype stage. For most users, a 128GB or 256GB model strikes the perfect balance between price and capacity. If more space is required, a 512GB card might be more practical and usually provides a superior cost-per-GB ratio. In the market, a good 128GB card can be found for around $15 or less, while a decent 256GB card may cost less than $30, and a decent 512GB card can be as little as $40 (though, generally, they cost closer to $50 or $60). The cost significantly increases for 1TB cards, typically at around $100. It is to be noted that the card’s performance may vary depending on the capacity. For instance, SanDisk states that its 128GB Extreme card provides sequential write speeds of up to 90 MB/s, while higher-capacity models offer up to 130 MB/s.
When discussing microSD cards, we primarily refer to cards utilizing the microSDXC standard, ranging from 32GB to 2TB. It is essential to verify if your device is compatible with this standard as some older devices may only work with microSDHC cards, which have capacities of 2GB to 32GB. Nonetheless, compatibility is seldom a concern nowadays.
Read and Write Speeds
MicroSD cards are predominantly evaluated based on their read and write speeds, typically measured in megabytes per second. In general, most microSD cards have a faster read speed than a write speed. These speeds can be further categorized into sequential and random performance. The former is critical when accessing or saving long, consistent streams of data, such as opening a large video or copying files from a PC. Random performance, on the other hand, involves how swiftly a card can read and write small files scattered throughout the device. While these speeds may not be advertised prominently, they are crucial when using a card with a gaming device or a single-board computer like the Raspberry Pi.
MicroSD cards display various numbers, letters, and symbols denoting their speed class and performance ratings, determined by the SD Association. The Video Speed Class (V-rating) states the card’s minimum sequential write speed, ranging from V6 to V90. A majority of the tested cards were V30-rated, with a sequential write speed of at least 30 MB/s. UHS Speed Class (U-rating) is divided into U3 (minimum of 30 MB/s write speed) and U1 (rated for 10 MB/s). Another classification, the Application Performance spec (A-rating), is measured in input/output operations per second (IOPS) and has two categories, A1 and A2, with varying read and write speeds. While many V30 cards offer higher write speeds than the minimum required and some A1 cards can outperform A2 models, in practice, it is advisable for most users to opt for a card with V30, U3, and A2 ratings.
UHS Bus Speeds
MicroSD cards utilize the UHS-I and UHS-II interfaces, with UHS-II cards generally being the fastest but also more expensive. For most users, UHS-I options are sufficient, especially considering the spotty stock and compatibility requirements for UHS-II cards.
Many microSD cards are designed to be durable, backed by a long warranty. It is recommended to consider the warranty with endurance cards, which are capable of withstanding more hours of writing.
Purchasing from reputable retailers such as Best Buy, B&H Photo, Adorama, or Amazon is recommended to avoid counterfeit products. It is also advised to be wary of unusually low prices, as they may indicate counterfeit products.