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We bought 11 of the best micro sd cards and timed large and small file transfer speeds, recorded hours of 4K video, and shot bursts of memory-intensive RAW photos until the cards reached their speed limits.
When you're documenting life in photos, audio, or video, you want your device to capture high-resolution, rapid-fire data. That means you need an SD card that can write that data quickly. If it doesn't, you may miss something. The Kingston 128GB microSDXC Canvas Go Plus outperformed the rest in our large and small file write speed tests, making it an excellent choice for anyone looking for top-notch performance. It wrote large files, like the 5 GB 4K video we used in testing, at an average rate of 101 megabytes per second (MBps), and transferred smaller files, like our 2 GB test folder of RAW photos, at a rate of 30 MBps. Its read speeds are also respectable, allowing you to import information, like games or photos, to your device quickly.
With storage options reaching up to 512 gigabytes (GB), you can capture up to 17 hours of 4k video and 6,400 RAW photos using the Canvas Go Plus (assuming the photos are around 24 megapixels), according to Kingston. That's plenty for most applications, especially since memory cards aren't ideal for long-term data storage. If you import massive amounts of data to your computer to process, you might want a card with faster read speeds. The SanDisk 64GB Extreme MicroSD and SanDisk 128GB MicroSDXC for Nintendo Switch take less time to import data to your computer. And both have write speeds that compete with the Canvas Go Plus. If you're looking for the fastest write speeds so you don't miss a moment, and can settle for marginally slower transfer speeds, this is an excellent option.
The Canvas Go Plus offers the best all-around performance of any card we tested.
The SanDisk 64GB Extreme Pro MicroSDXC is another fast-writing SD card. It 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 106 MBps. For those who like gadgets, this card meets the often strict minimum speed requirements for most drones. If you're capturing large media files, the SanDisk Extreme Pro won't hold you back. It also offers some of the fastest downloading, or read speeds, in the test (from 75 to 164 MBps), making it an excellent option for processing photos or importing games.
The Extreme Pro's large file write speeds exceed our top recommendation, the Kingston microSDXC Canvas Go Plus. But its small file write speeds are slower, measuring around 20 MBps. Both cards performed similarly in our burst mode photo shoot though, so you shouldn't lose much practical performance. The SanDisk 128GB MicroSDXC for Nintendo Switch is another option with top-tier read speeds and respectable writing rates. It comes with up to 256 GB of storage, which is adequate, but far from impressive these days. The Extreme Pro stores up to 400 GB. It's plenty for most applications but pales in comparison to cards that hold up to a terabyte (TB). If you don't need to hold massive amounts of data in short-term storage, this is the best balance of write and read speeds in the test.
The SanDisk Extreme Pro is fast and up for pretty much any task.
If you want fast data transfer speeds for less, the SanDisk 64GB Extreme MicroSD is a great bet. Its measured large file write speed of 83 MBps and V30 video speed rating allow it to record 4K video easily. It also withstood a full 5 seconds in our tortuous burst mode RAW photo shoot test and is fast enough to use in most consumer camera drones. Keep in mind that you should always check the device's specs first. Standards change quickly. Perhaps best of all, SanDisk Extreme is a solid value, offering faster transfer speeds for less.
If you want to take advantage of this card's largest storage option, which is a full terabyte (TB), you'll pay quite a bit more. If you need to prioritize your budget, the SanDisk Ultra microSDXC's could be a good option. Its transfer speeds are slower, but the 1 TB option is less expensive than the SanDisk Extreme. If you need speed and a reasonable amount of storage at a reasonable price, the SanDisk Extreme might be your perfect compromise.
The SanDisk Extreme offers plenty of speed and impressive prices.
If you're on a budget, the Amazon Basics microSDXC two-pack is a compelling option, with top-notch write speeds and plenty of storage at the 256 GB tier we tested. In our tests, the maximum write speed of 83 MBps lets us easily capture high-quality 4K videos. The 27 MBps small file write speeds are fast enough to capture RAW photos in rapid-fire succession. You can also get up to a terabyte of storage, though you start to lose some of the cost savings at the higher price tiers. The higher storage options of the SanDisk Ultra microSDXC often cost less. The Ultra is slower to write but faster to read than the Amazon Basics cards.
The Amazon Basic's reasonable read speeds (ranging from 58 MBps for groups of small files to 89 MBps for single large files) let us view the photos and videos we saved to the card without much delay. That said, many cards we tested read and write files faster. The SanDisk 64GB Extreme MicroSD and Lexar Professional 1066x 64GB microSDXC can also cost less if you only need a single card. (The SanDisk Extreme is faster, but both work well.) If you need a card that writes quickly enough, want to save your pennies, and can compromise on how long it takes to download the files later on, consider the Amazon Basics microSDXC.
Reasonable prices, fast write speeds, and a wide range of storage options make the Amazon Basic's card a solid option.
Credit: Clark Tate
Compare Products
At GearLab, we conduct side-by-side tests to find which products are the best.
Credit: Ross Patton
Why Trust GearLab
Our microSD card review relies on a mix of objective measurements in the lab and real-world performance tests. We measure each card's speed while writing and reading large video files and folders full of photos. We corroborate these results with functional tests — recording 4K video, shooting bursts of memory-intensive RAW images, and expanding the storage of our phones and other devices. Our extensive testing period puts these cards through 60 individual tests to find the very best for each application.
We break down our overall score into four key metrics:
Large File Write Speed (30% of overall score weighting)
Small File Write Speed (30% weighting)
Average Read Speed (30% weighting)
Storage Range (10% weighting)
Our in-house photographers, Laura Casner and Jason Peters helped design our microSD testing processes. These professionals have decades of photography and videography experience and have used just about every form of solid-state memory card currently available.
Senior Editors Max Mutter and 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 and are intensely 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.
Review Editor Clark Tate joins the team after studying digital photography at the Maine College of Art & Design and earning a graduate certificate a the Salt Institute for Documentary Studies. Clark uses SD cards to capture photos, film, and audio for various journalistic and documentary projects and uses her background in science to objectively test and document each option's performance.
Though they look similar and seem interchangeable, these cards vary widely in their performance.
Credit: Clark Tate
Analysis and Test Results
Write speed, or the speed at which a card can record data, is the most variable and differentiating aspect of microSD cards. These speeds vary significantly depending on the types of files being written. So we tested large file write speed, or how quickly a card can write a single large video file, and small file write speed, or how quickly a card can write groups of smaller files like RAW photos.
We also tested read speeds, or how quickly cards can transfer their data back onto your device. These are more important for gamers who don't want to wait for their stored games to download to their device, or for photographers or filmmakers looking to minimize their processing time. Most microSD cards are pretty good at reading files, so we put more emphasis on write speeds to separate the good cards from the great ones.
Memory cards are covered in abbreviations that tell you which minimum industry standards they meet. They provide useful information if you know what they mean.
Credit: Clark Tate
SD Card Terms — An Overview
SD Cards evolve quickly and those tiny numbers, letters, and acronyms can be downright maddening. But, to date, they're the best way for manufacturers to communicate a card's capabilities. Many of these standards are set and promoted by the SD Association. Their website is a good place to take an SD deep dive if you don't mind long, detailed explanations. If you do, here's a summary –
Speed Class, or Class rating — One of the earliest speed ratings, this one is fairly outdated. All the cards we tested are Class 10 and are capable of transferring data at a minimum of 10 MBps. UHS Speed Class, or U rating — This was the original writing speed standard for video. A U1 card will write at least 10 MBps, and a U3 writes at a minimum of 30 MBps. Both will record 1080p video or a lower frame rate 4K video. You need a U3 or V30 rating to shoot smooth, high-frame-rate, high-definition videos. Video Speed Class, or V rating — As cards have evolved, the Video Speed Class Rating (V rating) has become more important than the UHS Speed Class. A rating of V10 works for 1080p and slower 4K frame rates. V30 (or at least 30 MBps) will capture higher definition 4K, and V60 and V90 (60 MBps and 90 MBps respectively) can handle 8K video with UHS-I or UHSII Bus Interfaces (discussed below). SD Express Speed Class — This is a new classification with minimum transfer speeds ranging from 150 MBps to 600 MBps. We haven't tested cards with this rating. Application Performance Class, or A rating — This classification defines minimum performance standards for cards used to store your apps or the data they need. A2 is more capable than A1. Bus Interfaces — The bus interface, or UHS number, refers to how many rows of data transfer terminals are on an SD card. UHS-I cards have one row. UHS-II cards have two, which makes them much faster. This is a relatively new technology. If your camera or phone lacks the corresponding pins, a UHS-II card will be limited to UHS-I speeds. There are no UHS-II cards in this review currently.
The physical difference between UHS-I (left) and UHS-II (right) technology is that UHS-II cards have an additional row of terminals.
Credit: Ross Patton
What's the Best Value?
One of our primary goals here at GearLab is to find products that offer top-notch performance at less than top-tier prices. We don't want you to waste your hard-earned money. Luckily, there are a lot of solid deals in the microSD world. Our favorite budget-friendly card is the Amazon Basics microSDXC two-pack. It's impressive write speeds will help you capture fast-paced photography and high-quality 4K video. Though its read speeds are slower than our favorite options, it comes in a massive range of storage options, up to 1 TB.
Credit: Clark Tate
The SanDisk 64GB Extreme MicroSD also offers excellent value, with some of the fastest read speeds in the test. That's great if you need quick turnaround processing times. It also writes large files quickly, and so works well for high-def video and photography. For a few dollars more, the SanDisk 64GB Extreme Pro MicroSDXC offers an increase in large file write 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 any of these high-value options.
The SanDisk 64GB Extreme MicroSD is plenty fast enough for action cameras despite its low cost.
Credit: Ross Patton
Large File Write Speed
Whether or not a microSD card's large file write speed is important to you depends on the type of data you need to capture. If you need a microSD card for a home security camera or as a compact way to back up text and photo files, you can get away with slower large file write speeds. Small file write speeds will be more important to you. If you want to capture a high frame rate, 4K or 8K vidoes, this is the most important metric to consider.
Adequate large file write speeds record high-quality videos without dropping frames or pixelating the image. To measure large file write speed, we timed how long it took to transfer a 5GB 1080p video file onto each card. This allowed us to calculate speeds in megabytes per second (MBps). Large files are the easiest for solid-state storage devices like microSD cards to write, so a card's measured large file write speed is probably its maximum write speed overall.
We also recorded 5 minutes of 4K video on each card with the same camera. This is a pass/fail test — a card that dropped any frames or showed any pixelation resulted in a fail. All of the cards that made our final cut in this review passed the test.
The Kingston 128GB microSDXC Canvas Go Plus and SanDisk 64GB Extreme Pro MicroSDXC posted the fastest large file write speeds in the test, measured at 101 and 106 MBps respectively. Only a sliver behind these models is the SanDisk 128GB MicroSDXC for Nintendo Switch, which reached top transfer speeds of 97 MBps.
Kingston's 128GB Canvas Go! Plus card had the fastest large file write speeds in the test.
Credit: Clark Tate
The Amazon Basics microSDXC, SanDisk 64GB Extreme microSD, and PNY 128GB Elite-X microSDXC all performed impressively, topping out at 83 MBps.
We used a range of devices to test these cards, from audio recorders to digital cameras to drones.
Credit: Clark Tate
Small File Write Speed
While large file write speeds impact videographers, small file write speeds can be more important for photographers. That's because small file write speed measures a card's ability to process and save many files in rapid succession. This is a more complicated task than moving one large file. Small file speeds are much slower as a result.
To test this metric, we timed the transfer of nearly 4,000 photos representing 2 GB of data to each card. Then we recorded a full-speed burst of RAW photos onto each card until it started to lag. We recorded the shutter speed using a microphone and analyzed the resulting waveform, counting how many images each card could write before reaching its limit and slowing down.
The Canvas Go Plus, shown here in an adapter that allows you to use it as a full-size SD card, has the fastest small file right speed in the test, making it a good choice for digital photographers.
Credit: Clark Tate
The Kingston 128GB microSDXC Canvas Go Plus card earned the top speed score in this metric, which we measured at 30 MBps. If you recall, this card's large file write speed is 101 MBps, underscoring how much harder it is for these cards to many small files. The range of performance is much narrower as a result. The second and third fastest options, the Amazon Basics MicroSDXC and PNY 128GB Elite-X microSDXC, transfer 27 and 25 MBps respectively.
All of these cards can capture 6 RAW photos in burst mode before slowing slightly. Then they held a faster pace longer than most of the lower-scoring cards. The SanDisk 128GB MicroSDXC for Nintendo Switch and SanDisk 64 GB Extreme Pro MicroSDXC performed similarly in the photoshoot test. This is despite a drop of in measured small file transfer rates, which we measured at 21 and 20 MBps respectively.
The Lexar Professional 1066x 64GB microSDXC posted a slightly higher score of 22 MBps but slowed more dramatically after the initial burst of 6 photos than the higher ranking cards in this metric.
The Amazon Basics MicroSDXC card offers top-notch small file write speeds.
This well-rounded PNY MicroSD card stands out with one of the fastest small file write speeds in the test.
The SanDisk 64GB Extreme MicroSD clocked in at 18 MBps, the Samsung 128GB EVO Plus MicroSDXC at 17 MBps, and the SanDisk Ultra 128GB microSDXC was just behind at 15 MBps. Then there's a step down to the Samsung 128 GB PRO Endurance Micro SDHC and SanDisk 16GB Ultra MicroSDHC, which we measured at 10 and 9 MBps respectively.
All of these cards were able to take at least 5 rapid-fire photos in our RAW image burst test. Only the SanDisk 16GB Ultra slowed down significantly afterwards. Which is to say, all of these cards are quite capable of capturing photos in most situations. If you want to capture fast-paced subjects like bike racers or wildlife, you'll probably want one of the higher-scoring options.
Comparing the RAW image burst test results of one of the fastest cards (above) and one of the slowest (below)
Average Read Speed
Read speeds refer to how quickly you can extract data from a card, like when importing vacation photos and videos to your computer. We tested both large and small file read speeds by transferring the same video and photo files used in our write speed tests. We averaged the results in one metric because read speeds are usually faster than write speeds, making them less informative when you're judging a card's performance.
And, while sitting at your comfortable desk watching files transfer is boring, fast write speeds let you capture the files in the first place, making them more critical to most missions. If you regularly work with scads of media files though, those extra moments waiting for downloads can add up. If you want to salvage that time, this metric is particularly important.
The SanDisk 128 GB MicroSDXC for Nintendo Switch came out on top, with an average reach speed of 121 MBps — a blistering 168 MBps for large files and a respectable 75 MBps for many small files. Since this card is meant to store games that you can then download and play, it makes sense that it prioritizes read speeds.
The SanDisk MicroSDXC for Nintendo Switch has the fastest read speed in the test, which comes in handing when importing stored games.
Credit: Jason Peters
The SanDisk 64 GB Extreme MicroSD and the Pro MicroSDXC version are just behind with average read speeds of 120 and 119 MBps. Since all of these options also posted impressive write speeds, they are excellent choices for all-around performance.
The next tier down is nearly as impressive, with the Lexar Professional 1066x 64GB microSDXC averaging a 116 MBps read speed. We measured the SanDisk Ultra 128GB microSDXC at 113 MBps and the Kingston 128GB microSDXC Canvas Go Plus at 107 MBps. At this performance level and above, we never noticed an annoying lag in performance.
The read speeds drop off from there. Three cards read at an average of 74 MBps — the Amazon Basics MicroSDXC, PNY 128 GB Elite-X MicroSD, Samsung 128 GB EVO Plus MicroSDXC. The SanDisk 16 GB Ultra MicroSDHC came in at 71 MBps. The Samsung 128 GB PRO Endurance MicroSDHC averaged 65 MBps, with a small file read speed of 38 MBps. That makes its transfer times noticeable, and maybe a bit annoying.
It makes sense that a memory card made specifically for the Nintendo Switch prioritizes fast read speeds to make sure you get your games in record time. Be sure to look for a card that meets your needs.
Credit: Clark Tate
Storage
While we only tested a single storage option for each microSD card (striving to test the most useful and popular sizes), we did take into account how many storage options are available. Card capacity has steadily increased over the years, and several options in the test are available with up to 1,000 GB, or one terabyte (TB). That's enough to hold about 333,333 songs, 2,083 minutes of 4K video, or 12,800 RAW photos, according to Kingston Technology.
You can purchase the SanDisk 64GB Extreme MicroSD, Amazon Basics microSDXC, and SanDisk Ultra 128GB microSDXC with up to 1 TB of storage, though it will cost more than the versions we tested and link to. We've noticed that the large storage options for the SanDisk Ultra often costs less than the rest.
The next tier of storage space goes up to 512 GB, holding about half as much as the 1 TB options. These cards include the Kingston 128GB microSDXC Canvas Go Plus, Lexar Professional 1066x 64GB microSDXC, Samsung 128GB EVO Plus MicroSDXC, and SanDisk 16GB Ultra MicroSDHC. The SanDisk 64 GB Extreme Pro MicroSDXC is available with up to 400 GB of storage.
Keep in mind that more storage isn't always better. The Samsung EVO is available in a 32 GB version, and some devices, like trail cameras, only accept cards that hold that much data.
Credit: Clark Tate
The SanDisk MicroSDXC for Nintendo Switch and PNY Elite-X MicroSDXC are available in a narrow size range from 64, 128, or 256 GB. The largest versions will hold roughly half of what a 512 GB card can and a fourth of the usable space in a 1 TB card. The Samsung PRO Endurance MicroSDHC offers up to 128 GB of storage.
Of course, some devices, like trail cameras, only work with small storage sizes, often 32 GB. The Kingston Canvas Go Plus MicroSDXC, SanDisk Extreme MicroSD, SanDisk Ultra MicroSDXC, and Samsung EVO Plus MicroSDXC are all available in that size.
We hope you feel more prepared to decipher the information printed on these cards.
Credit: Clark Tate
Conclusion
MicroSD cards may seem inscrutable and interchangeable, but if you look beyond their fragile plastic frames, they have noticeable differences. We took a deep dive to find each differentiating feature and rank the cards based on your needs. We hope the results of our extensive testing help you wade through the myriad industry standards and marketing claims. With any luck, our review will lead you to the best product for your needs and budget.
