Best Micro SD Card of 2020
Looking for a microSD that won't leave you wanting for speed? Look no further than the SanDisk 64GB Extreme Pro MicroSDXC. It easily handled every task we threw at it in our testing, from 4K video shoots to rapid-fire RAW images, and reached an impressive maximum write speed of 86 mb/s. For those of you that like gadgets, this card notably meets the often stingy minimum speed requirements of the vast majority of drones. Essentially, if you go with the SanDisk Extreme Pro, you're likely never going to have to worry about the speed of your card. You won't have to worry about adverse conditions either, as SanDisk reports the card to be water, temperature, shock, and X-ray proof, and backs that claim up with a limited lifetime warranty.
All of this performance doesn't come for free, as the SanDisk Extreme Pro is noticeably more expensive than the average card on the market. However, that price difference is relatively small in comparison to the increase in performance. We think for most people the small extra cost will be well worth the reliability and versatility afforded by the extra speed.
Unless you're using a fancy camera drone or dabbling in advanced photography techniques, chances are you can get away with a somewhat less than agile card. If that's the case, we think the Samsung 32GB EVO Select MicroSDHC offers a great value. Though its maximum measured write speed of 35 mb/s is only mediocre, it is more than fast enough for most tasks. In fact, in our tests it was easily able to record 4K video and even shoot bursts of RAW images for a short period, so you should have no issues using it in a phone or security camera. The card also carries a guarantee of being water, shock, temperature, and X-ray proof. You get all this at a relatively good value, particularly if you consider some of the higher-capacity options.
Across the board the EVO Select posted below average speeds in our tests. In a functional sense this mostly showed up in our RAW image burst tests, where the EVO Select could only shoot for a few seconds before getting bogged down. Its specs are also such that the software of speed-sensitive things like drones may not be compatible. Finally, its limited 10 year warranty that excludes "write intensive" uses like dash cameras is more restricted than most. Despite these drawbacks, the EVO Select still provides a good bang for the buck.
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. Not only does it provide a lot of storage at a relatively reasonable price, it is fast enough that you probably won't even 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 lagging or delays. Plus it enjoys SanDisk's standard limited lifetime warranty.
The lack of a standard SD card converter is the main drawback we can point to with this card. We did find the need to purchase a converter separately in order to use a full-sized SD card reader to be a bit of a pain. 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 is a pleasant surprise. For phone and tablet storage expansion, you can't do much better than the SanDisk 128GB MicroSDXC for Nintendo Switch.
For particularly speed-hungry tasks like advanced photography or videography, it may be worth investing in an ultra high speed class 2 (UHS-II) card. If you want to go that route, we think the Lexar Professional 1800x 64GB MicroSDXC UHS-II is the best option. In our tests it posted a maximum write speed of 125 mb/s, the fastest such figure we've measured. That measured speed translated into all of our real-world tests, as it easily handled RAW burst shooting and 4K video recording. As you'd expect from such a high-quality card, it is backed up by a limited lifetime warranty.
Like any UHS-II card, the Lexar Professional 1800x is quite pricey. Also like any other UHS-II card, you need compatible equipment in order to access its full speeds. Most cameras and other devices that can take advantage of the UHS-II format use full-sized SD card slots. The Lexar Professional 1800x comes with a converter so it can be used in such slots. However, it is slower than the full-sized UHS-II cards we've tested, so some people may be better off with a full-sized card. However, if you do happen to have a UHS-II microSD card compatible device, the Lexar Professional 1800x is the best option we've found.
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 easily record 4K video in our tests, and it lasted a full 5 seconds in our RAW image burst shooting torture test. It is also likely to be fast enough for use in most consumer camera drones, though you should definitely check the specs first. As you'd expect from one of SanDisk's upper-tier cards, it is touted as water, shock, temperature, and X-ray proof, and comes with a limited lifetime warranty.
The SanDisk Extreme is cheaper than the faster cards on the market, but not by much. If you're concerned about speed, you'll likely want to spend the extra few 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 whatever device you're using, the SanDisk Extreme may be a perfect compromise.
The Samsung 128GB PRO Endurance MicroSDHC offers a lot of storage space for a relatively low price. It is designed for continuous recording devices, such as security or dashboard cameras, and that extra storage is perfect for those applications. The 41 mb/s speed is plenty for its intended use and we even found it suitable for 4K recording. Samsung advertises the card as water, magnet, temperature, and X-ray proof.
While this card is fast enough for most applications, it may lag a bit if used for advanced RAW photography, and may be too slow for some of the advanced consumer drones that require faster memory cards. The 3 year limited warranty is also less generous than most, but it does at least cover "write intensive" activities like continuous recording — an exception made in most of the company's other warranties. If you're looking for a lot of storage on the cheap, the Samsung PRO Endurance will likely meet your needs.
The Samsung 128GB EVO Plus MicroSDXC is a high-capacity card that displayed an elite write speed of 86 mb/s in our tests. This makes it suitable for pretty much any task you could throw at a memory card. Its higher capacity configurations are also a bit less expensive than those of other similarly fast models on the market. Like many cards, it sports a manufacturer claim of being impervious to water, temperature, magnetic fields, and X-rays.
Though this card offers more gigabytes per dollar than many of the faster cards available, it is still significantly more expensive than average. Additionally, we would expect a card of this caliber to offer at least a limited lifetime warranty. Alas, it only touts a limited 10 year warranty that is voided by "write intensive" uses like security and dashboard cameras. As long as you can deal with a slightly lackluster warranty, the Samsung EVO Plus can provide a combination of fast speeds and lots of storage for less than many of the competitors.
Basic tasks, like recording HD video from a security camera or taking standard photos, don't require much speed, allowing you to get away with a less expensive card. The SanDisk 16GB Ultra MicroSDHC can work well in such situations. Despite its measured write speed of 12 mb/s being somewhat glacial when compared to many other cards, it still managed to record 4K video in our tests without a glitch. Thus it will likely work well for most basic, non speed-intensive tasks.
The SanDisk Ultra doesn't leave much room for growth, and will likely bog down if you use it in more demanding situations/devices. It also comes with only a 10 year limited warranty, as opposed to the lifetime version that covers most of the company's other cards. If your SD card needs are fairly basic, the SanDisk Ultra is a relatively inexpensive option.
Why You Should Trust Us
We designed our microSD card testing processes with the help of our in-house photographers, Laura Casner and Jason Peters. These two photography and videography professionals have multiple decades of experience between them and have used just about every form of solid-state memory cards currently available. Senior Editor Max Mutter has been testing and writing about consumer technology products for nearly 5 years. In that time he's encountered and used more than 100 devices that require the use of microSD cards, making him intimately familiar with their uses, speed classes, and idiosyncrasies.
Our microSD card testing relies on a mix of objective measurements and real-world use. We measured each card's speed in both 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, to shoot bursts of memory-intensive RAW images, and to expand the storage of our phones and other devices.
Analysis and Test Results
Write speeds, or the speeds at which a card can onload data, are the most differentiating factors of microSD cards. These speeds can differ quite a bit depending on what types of files are being written. We focused our testing and ratings on 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 thus only important for more specific and less common situations.
Large File Write Speed
The ability to quickly write large files allows a card to record high-quality video without dropping any frames or running into any pixelation. To measure large file write speed we transferred the same 5GB 1080p video file onto each card and timed the process, allowing 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 we dubbed this measurement the maximum measured write speed. We then used each card to record 5 minutes of 4K video, all using the same camera, to see how well each 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.
The Lexar Professional 1800x 64GB microSDXC UHS-II topped our chart in large file write speed, logging an impressive 125 mb/s. This is substantially faster than most other cards, but it should be noted that you need UHS-II compatible devices in order to enjoy those full speeds. This means the card's maximum speed will be limited to around 90 mb/s in most devices with microSD slots.
The SanDisk 64GB Extreme Pro MicroSDXC was the fastest of the UHS-I cards that we tested, reaching a maximum speed of 86 mb/s. The Samsung 128GB EVO Plus MicroSDXC was able to match that speed in our tests. The SanDisk 128GB MicroSDXC for Nintendo Switch and the SanDisk 64GB Extreme microSD came close to these speeds, hitting clips of 70 and 67 mb/s in our tests, respectively.
Beyond this point we saw a significant drop off in terms of large file write speed. However, even the slowest cards were able to function well for basic uses like recording 1080p HD video. If you're conducting more advanced tasks or using devices like top-tier camera drones that require faster cards, you'll want to go with one of the top performers listed above.
Small File Write Speed
Small file write speed largely corresponds to a card's ability to quickly process and save many images in rapid succession. To test this we transferred the same 5GB folder full of almost 2000 photos onto each card, timing each transfer. 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 doing this we held a microphone up to the camera and recorded the audio onto a basic music production program. The resulting waveform provided a visual representation of how long each card could shoot at full speed before reaching its speed capacity and slowing down.
Three cards shared the top speed in this metric, with the SanDisk 64GB Extreme Pro MicroSDXC, the Samsung 128GB EVO Plus MicroSDXC, and the SanDisk 128GB MicroSDXC for Nintendo Switch all logging a top speed of 36 mb/s (small file speeds are generally slower than large file speeds). All these cards also lasted 5+ seconds in our RAW image burst test.
The Lexar Professional 1800x 64GB microSDXC UHS-II failed to leverage its advanced technology as much in our small file test, hitting a top speed of 29 mb/s. While this is still quite fast, we would have expected faster given its pedigree.
Beyond these top performers most cards fell into the 20 mb/s range. However, even the slowest card was able to last 3 seconds in our RAW image burst test, indicating that any card will be more than capable of handling basic imaging tasks.
Read speeds come into play when you are extracting data from a card, such as when uploading all the videos and photos you took on your vacation to a computer. 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.
Our read speed results were quite consistent across the board, with pretty much every card hitting speeds of about 94 mb/s when reading large files, and about 78 mb/s when reading groups of small files. The one difference came with the Lexar Professional 1800x 64GB microSDXC UHS-II, which utilized its additional hardware to reach speeds of 250 and 167 mb/s respectively. While this is substantially faster, it corresponds to relatively miniscule time savings in real world use. For example, it took the Lexar Professional 1800x 64GB microSDXC UHS-II 30 seconds to upload a 5GB folder of photos to a computer, while most of the other cards averaged just over a minute. Therefore, unless you're routinely uploading dozen of gigabytes of data to your computer, the extra speed of the Lexar Professional 1800x 64GB microSDXC UHS-II is likely not worth the extra cost.
MicroSD cards may seem a dime a dozen, but if you look under the hood there are actually noticeable differences. We hope our testing results have helped you wade through the sea of arcane stats and marketing claims that often accompany shopping for one of these cards and led you to the perfect choice for your intended use.
— Max Mutter