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To find the best microSD cards available today, we researched dozens of models before buying and testing the 12 most promising options side-by-side. Our tests included timing the transfers of large and small files, recording multiple hours of 4K video, and shooting bursts of RAW images until the cards finally reached their speed limits. If you're looking for an inexpensive way to expand your phone's storage or need a super-fast card for an advanced drone, our testing results will help you find the best microSD card for your needs and budget.
Anyone familiar with tech products knows that there's always a possibility that they will glitch, fail, or even just get lost, so it's never a bad idea to have multiple storage options to back up your files. Whether you're searching for the best USB flash drive, the top memory card for your trail camera, or the fastest external hard drive for storing your files, we've tested the most popular products on the market to help inform your purchase decisions.
Editor's Note: We updated our selection on November 17, 2023, by removing discontinued products.
Max measured write speed: 86 MBps | Available sizes (GB): 64, 128, 256, 400
REASONS TO BUY
Excellent write speeds
Great for 4K video and RAW photography
Meets speed requirements of almost any device
REASONS TO AVOID
Costs a bit more than average
Do you have a need for speed? For a fast-writing SD card, look no further than the SanDisk 64GB Extreme Pro MicroSDXC. This card easily handled every task we threw at it in our testing, from 4K video shoots to rapid-fire RAW images, and achieved an impressive maximum write speed of 86 mb/s. For those who like gadgets, this card notably meets the often strict minimum speed requirements of most drones. With the SanDisk Extreme Pro, you're likely never going to have to worry about the speed of your card.
All of this performance doesn't come for free, as the SanDisk Extreme Pro is noticeably more expensive than the average UHS-I card on the market. However, that price difference is relatively small in comparison to the performance benefits. The small extra cost will be well worth it for most people considering the reliability and versatility afforded by the extra speed.
Max measured write speed: 67 MBps | Available sizes (GB): 32, 64, 128, 256, 400, 512, 1000
REASONS TO BUY
Quite fast
Works well for 4K video and RAW photography
Costs slightly less than some other high-speed options
REASONS TO AVOID
Still more expensive than average
If you want a fast card but don't want to pay top dollar, the SanDisk 64GB Extreme MicroSD is a good option. Its measured write speed of 67 mb/s allowed it to record 4K video in our tests easily, and it withstood a full 5 seconds in our tortuous RAW image burst shooting test. It is also likely to be fast enough for use in most consumer camera drones, though we recommend checking the specs first.
The SanDisk Extreme is cheaper than the faster UHS-I cards on the market, but not by much. If you're concerned about speed, you'll likely want to spend a few extra dollars to get the best. However, if you want to save a few bucks and get the cheapest card that meets the minimum speed specs of the device you're using, the SanDisk Extreme might be a perfect compromise.
Max measured write speed: 70 MBps | Available sizes (GB): 64, 128, 256
REASONS TO BUY
Very fast write speeds
Good read speeds
REASONS TO AVOID
Doesn't come with a converter
MicroSD cards are a cheap and effective way to instantly upgrade the internal storage of your phone or tablet (unfortunately, most Apple devices don't offer such an option). If that's your main goal, the SanDisk 128GB MicroSDXC for Nintendo Switch is a near-perfect solution. It provides a lot of storage at a relatively reasonable price, and it's fast enough that you probably won't notice you're accessing your files from an 'external' storage device. In our tests, the maximum write speed of 70 mb/s allowed us to quickly offload photos and videos from our phones to free up space, and the solid read speeds let us view those same photos and videos without any lag or delays.
The lack of a standard SD card converter is the main drawback of this card. It's annoying to have to purchase a converter separately to use this with a full-sized SD card reader. However, if you're sure you'll only be using the card in your phone or tablet, the lack of an extra piece of plastic may not be a big deal. For phone or tablet storage expansion, you can't do much better than the SanDisk MicroSDXC for Nintendo Switch.
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Why Trust GearLab
Our microSD card testing relies on a mix of objective measurements and judgment of performance in real-world situations. We measured each card's speed while writing and reading the same large video files and the same folders full of photos, providing us with directly comparable speed measurements. We then corroborated these results with functional tests: using each card to record 4K video, shoot bursts of memory-intensive RAW images, and expand the storage of our phones and other devices. Our extensive testing period puts these cards through 60 individual tests to parse out the very best options.
We break down our overall score into three key metrics:
Large File Write Speed (40% of overall score weighting)
Small File Write Speed (40% weighting)
Read Speed (20% weighting)
We designed our microSD card testing processes with the help of our in-house photographers, Laura Casner and Jason Peters. These two professionals have multiple decades of photography and videography experience between them and have used just about every form of solid-state memory card currently available. Senior Editor Max Mutter and Review Editor Ross Patton have been testing and writing about consumer technology products for a combined total of ten years. In that time, they've used more than 100 devices that require microSD cards, so they are intimately familiar with their functions, speed classes, and idiosyncrasies. In his free time, Max has become an avid drone pilot, while Ross has been recording and editing digital video since consumer video products shifted from film to top-notch memory cards.
Analysis and Test Results
Write speed, or the speed at which a card can record data, is the most differentiating factor of microSD cards. These speeds can also differ quite a bit depending on what types of files are being written. We focused our testing and ratings on two performance areas: large file write speed, or how quickly a card can write video files, and small file write speed, or how quickly a card can write groups of smaller files like photos. We also tested and considered read speeds or how quickly cards can transfer existing data. However, read speeds are less differentiating and usually only important for more niche situations.
A Brief Explanation of Bus Interfaces
While shopping for microSD cards, you'll see many technical specifications that differentiate the cards from one another. Some refer to the capacity, some refer to the purpose for which the card was designed, and some refer to speed. Arguably the most important spec is the bus interface or UHS number. As far as hardware goes, a UHS-II card has an extra row of terminals that allow for a more efficient transfer of data.
However, this is a relatively new technology, so it isn't widely supported on the device end. If your camera, phone, or reader lacks the corresponding pins for the extra set of terminals, a UHS-II card will be limited to UHS-I speeds. The faster UHS-II cards with the extra terminals are primarily used by professional videographers and photographers carrying cutting-edge, high-dollar equipment.
Value
One of our primary goals at GearLab is to identify which products offer the best performance at the lowest price, thus preventing our readers from wasting their hard-earned money. For the most part, the top-tier microSD cards are the most expensive, but most people don't need the best of the best. Our favorite budget-friendly card, the SanDisk 64GB Extreme MicroSD, outperforms pricier options in several ways, and adequately captures 4K video. For a few dollars more, the SanDisk 64GB Extreme Pro MicroSDXC offers an increase in speeds. This is an ideal card for those using consumer-level drones and action cameras. If you have a phone or a handheld gaming console with a microSD expansion slot, you can add a substantial amount of memory for a reasonable price with the SanDisk 128GB MicroSDXC for Nintendo Switch. If you own a camera with a UHS-II microSD slot, you likely already know that UHS-II cards tend to carry a hefty price tag.
Large File Write Speed
Whether or not you need to consider a microSD card's large file write speeds wholly depends on what type of data you need to capture. If your new microSD card is for a home security camera or will be used as a compact way to back up text documents, large file write speed isn't an important consideration. But if you are looking to shoot long clips of super-slow motion 4K or 8K videos, pay attention to this metric.
The ability to quickly write large files can allow a card to record high-quality video without dropping any frames or resulting in any pixelation. To measure large file write speed, we transferred the same 5GB 1080p video file onto each card and timed the process. This allowed us to calculate a speed in megabytes per second (MB/s). Large files are the easiest for solid-state storage devices like microSD cards to write; therefore, this is likely the maximum measured write speed overall. We then used each card to record 5 minutes of 4K video, all with the same camera, to see how well each card worked in real-world scenarios. This latter test was conducted in a pass/fail manner; any dropped frames or pixelation resulted in a fail. All of the cards that made our final cut passed this test.
It comes as no surprise that the UHS-II cards showed the best results for this assessment. The Lexar 256GB microSDXC UHS-II clocked a rate of 129 MB/s. The Kingston 128GB microSDXC Canvas Go Plus, showed the fastest large file write speed for cards of its type with a maximum measured speed of 107 MB/s.
The SanDisk 64GB Extreme Pro MicroSDXC and Samsung 128GB EVO Plus MicroSDXC were the next fastest of the UHS-I cards that we tested, reaching a maximum speed of 86 MB/s. Only a sliver behind these models, the Amazon Basics microSDXC showed a top rate of 85 MB/s. The SanDisk 128GB MicroSDXC for Nintendo Switch and the SanDisk 64GB Extreme microSD came close to these speeds, hitting respective clips of 70 and 67 MB/s in our tests. Beyond this point, we saw a significant drop-off regarding large file write speed. However, even the slowest cards functioned well for basic uses like recording 1080p HD video.
Small File Write Speed
Small file write speed largely corresponds to a card's ability to quickly process and save many files in rapid succession. While large file write speeds are more of a concern for videographers, small file write speed is more important for photographers. To generate data for this metric, we transferred the same two-gigabyte folder filled with almost 4000 photos onto each card and timed each transfer. It is important to note that small file speeds are generally slower than large file speeds.
We then put each card into the same camera and shot a burst of RAW images at full speed until the card started to lag and bog down. While performing this test, we held a microphone near the camera and recorded the sound of the shutter onto a basic music production program. The resulting waveform provided a visual representation of how many images each card could write in rapid succession before reaching its limit and slowing down.
Three UHS-I cards share the top speed score in this metric. The SanDisk 64GB Extreme Pro MicroSDXC, the Samsung 128GB EVO Plus MicroSDXC, and the SanDisk 128GB MicroSDXC for Nintendo Switch all logged a top speed of 36 MB/s. The SanDisk 64GB Extreme MicroSD showed a slightly slower rate of 32 MB/s. All these cards also lasted more than five seconds in our RAW image burst test.
Beyond these top performers, most cards fell into the 20 MB/s range; the best card in this tier is the Kingston 128GB microSDXC Canvas Go Plus at 26 MB/s. The Amazon Basics microSDXC put up a speed of 23 MB/s. The remaining model's speeds range from 17 MB/s all the way down to 6MB/s. Even the slowest card, however, was able to last 3 seconds in our RAW image burst test. This proves that any of these cards should be more than capable of handling the imaging tasks of most users.
Read Speeds
Read speeds come into play when you are extracting data from a card, like when you are uploading all the videos and photos you took on your vacation to a computer. For those folks who regularly work with large files or large amounts of small files, those extra minutes of watching a file slowly transfer can add up. We tested read speeds by transferring the same video and photo files we used in our write speed tests from each card onto the same computer, using the same card reader.
The SanDisk Ultra 128GB microSDXC came out on top with an average read speed of 147 MB/s — by far the fastest UHS-I card we tested. The Lexar 256GB microSDXC UHS-II is relatively quick at reading as well, with an average speed of 131 MB/s.
The read speeds took a fairly substantial dive after the Lexar microSDXC UHS-II. The next fastest model was the Kingston 128GB microSDXC Canvas Go Plus with a speed of 94 MB/s. The only other model that made it into the 90s was the Amazon Basics microSDXC at 91 MB/s. The SanDisk 64GB Extreme Pro MicroSDXC and the Samsung 128GB EVO Plus MicroSDXC put up transfer rates of 88 MB/s and 87 MB/s, respectively. Three models tied at 86 MB/s — the SanDisk 128GB MicroSDXC for Nintendo Switch, and the Samsung 128GB PRO Endurance MicroSDHC. Finally, the SanDisk 16GB Ultra MicroSDHC stands alone at the bottom of the pack with an average read speed of 85 MB/s.
Conclusion
MicroSD cards may seem a dime a dozen, but if you look under their fragile plastic frames, there are actually noticeable differences. We took a deep dive to find these differentiating features and rank the options relative to one another. We hope our test results help you wade through the sea of arcane stats and marketing claims that often accompany these cards, and that our review leads you to the best product for your needs and budget.