MicroSD Memory Cards Speed Comparisons – 35 Tested

When selecting the best Micro SD memory cards, consider key factors such as capacity, read/write speeds, device compatibility, and price. Many brands offer various options to tailor the card’s capabilities to the user’s needs. 

The specific use case for your MicroSD memory card is crucial. Here are some use cases.

• Action Cameras / Drones: You’ll want a good minimum write speed card, U3 or V30, to handle the video data rate. This data will be written sequentially, and A1 or A2, along with the random read-write speeds, will not matter.
• Security Cameras: You’ll want a larger card with higher endurance. Since these cards are often written to, they must have nice endurance ratings so the flash doesn’t wear out quickly.
• Handheld Consoles: Consoles like the Odin 2 or Retroid Pocket 5 typically have relatively slow bus speeds. Sometimes, speeds are limited to around 40MB/s, depending on the console. For these consoles, you’ll want cards with good read and write speeds, as well as fast random read and write speeds. The Nintendo Switch 2 requires MicroSD Express cards.

Quick note: It’s essential to distinguish between microSD memory cards and full-sized SD memory cards, as most microSD cards come with an adapter that allows them to be used in a regular SD card slot. However, you may experience some inconsistencies with speed and disconnects when using microSD cards with SD card adapters, and I don’t recommend using them as a long-term solution.

Fastest Micro SD Memory Cards

These sequential read and write speed benchmarks were taken with the AJA System Test software on a Windows 11 Machine with a ProGrade Memory USB-C 10 Gbps card reader. Results are based on file size and resolution of 5120×2700 5k Red (16-bit RGBA), with speeds listed in megabytes per second.

The random read and write speeds were taken with Android 13 in the Retroid Pocket 5. Since it shows all the benchmarks.

Memory Card Ratings and Number: What It All Means

Understanding all the numbers, letters, and ratings on memory cards can be daunting. To make it easier, here is an overview of what you need to know about ratings and terminology for memory cards. With this information, shopping for memory cards will be a breeze!

EX

EX stands for Express, a new microSD card offering significantly faster read and write speeds, making it ideal for console gamers using the Nintendo Switch 2.

A1 vs A2

A1 and A2 memory cards are among the latest and most advanced in terms of random read and write speeds. Both offer exceptional storage expansion options and enable the use of specific applications. However, there are some differences between them that you should consider when deciding which is best for your needs.

A1

A1 memory cards were the first standard for improving random read and write speeds. They are guaranteed to achieve a minimum performance of 1500 IOPS when reading randomly, 500 IOPS when writing randomly, and an absolute minimum of 10 MB/s when writing or copying data.

A2

A2 Memory cards feature a data caching system that is ideal for applications with intensive random read and write operations. With a minimum random read speed of 4000 IOPS, a minimum random write speed of 2000 IOPS, and a sustained write speed of 10MB/s, these cards provide superior performance compared to other cards on the market.

What are IOPS?

What are IOPS? IOPs stand for Input/Output Operations Per Second, and they measure the speed and efficiency at which a storage device can access data. The higher the IOPS rating, the quicker a storage device can find and transfer small chunks of data, thus allowing applications to run more smoothly. When purchasing a storage card or hard drive, consider its IOPS to ensure optimal performance.

How do Micro SD Cards Compare to SSD drives?

When examining the performance of a Micro SD card as opposed to that of an SSD drive, it is clear that the latter offers much faster capabilities. For instance, the Samsung 850 PRO can achieve up to 100,000 IOPS (Input/Output Operations Per Second). Even with higher-end models, its IOPS count can reach 500,000; by comparison, a micro SD card may only be able to process 4,000 IOPS. Those seeking more advanced work on their mobile devices will benefit more from choosing an external SSD drive over a micro SD card.

U1 / U3 / V30 / V60 / V90

Memory cards are grouped into classes to indicate their guaranteed minimum write speeds. A U1 rating stands for a data transfer rate of 10 megabytes per second (MB/s), U3 is 30 MB/s, V30 is 30 MB/s, V60 provides 60 MB/s, and V90 is the highest at 90 MB/s. Older memory cards can be identified by looking for a circled 10 on the card; these cards have a write rate similar to that of a U1 card, with 10MB/s.

UHS-I vs UHS-II

UHS-I and UHS-II are two types of high-performance microSD cards with distinct features. UHS-I cards are more widely used in smartphones, tablets, and other devices due to their widespread accessibility across various devices. However, UHS-II memory cards offer increased speed by introducing a second data lane with an additional row of pins. This can significantly improve read/write speeds and IOPS, making these an ideal choice with cameras and high-bitrate video formats.

Best Micro SD Memory Card Conclusion

When choosing the best micro SD memory card, it’s important to consider speed, capacity, and compatibility. For most users, a high-speed UHS-I card with good performance and adequate storage should be plenty. However, if you need even faster read/write speeds and have a compatible device, UHS-II cards are your best bet. The best micro SD memory card will depend on your individual needs and budget, as well as the compatibility of your device.