• Ideal for Android-based smartphones and tablets
  • Transfer read speeds of up to 100MB/s (Based on internal testing; performance may be lower depending on host device, interface, usage conditions and other factors.)
  • Rated A1 for faster app performance (Results may vary based on host device, app type and other factors.)
  • UHS Speed Class U1 and Speed Class 10 for Full HD video recording and playback (Full HD (1920x1080) video support may vary based upon host device, file attributes, and other factors.)
  • Shockproof, temperature-proof, waterproof, and X-ray-proof (Card only)
  • 10-year limited manufacturer warranty

I love it! Works great in my Galaxy Note 8! Fast enough that I can throw pretty much anything at it. If you're wondering, modern Android versions (starting with Lollipop, as I recall) have the ability to read up to 1 TB of external storage. While this 400GB card is the maximum capacity you can currently buy*, the leading manufacturers are feverishly working to make larger capacity cards. For now, though, I think 400GB is enough to handle all the 4K video I can shoot. *- Don't be fooled by unscrupulous sellers, particularly on auction sites ( I won't name it because there are a lot of fake cards here, too), who list ridiculously large capacity cards for astonishingly low prices... you don't get what you pay for! They take cheap, generic cards, usually no more than 4 or 8 GB, and rewrite the card's firmware & re-label it to make it act and appear like a larger card... 256GB, 500GB or higher! There are tons of listings out there for 1 TERABYTE microSD cards! Of course there's no such thing: and when the physical memory of the card is reached, your device will simply start overwriting data... and your precious photos, videos and other files will be gone forever. In fact, one third of all SanDisk cards on the market are counterfeit! You can avoid all this by installing and using a free app called SD Insight to determine if your card is legitimate.

Good price and has been holding up well

This is a great card. Using it to actually run a disk intensive application as a portable test bed environment. Far, far faster than I expected to be, doing something that it wasn't necessarily designed for. I had tried other Speed Class 10 cards that were marginal, but this one met the need.

I got this 128 GIG card to use with my tablets. So far it has worked perfectly in my testing. I always keep a couple of spares around for my future buys and I seem to give a lot of my SD cards away to family and friends. I picked up this 128 GIG at a great price and I just couldn’t pass it up. I own about 100 SD cards and I always do a speed test to verify the reading and writing speeds before I install the memory. This card checked out extremely well. The fastest write speed on this card was 73.143 MB/Sec and the fastest reading speed was 93.368 MB/Sec. I have attached the graphical test data for your information. I used a USB 3.0 port with a USB 3.0 card reader for the test. Overall, this card worked well and I rated it five stars. If I have any future issues I will update my review. I hope my review and photo of the test data helps you. Out of 100 plus SD cards I have purchased from Sandisk I have only had one fail. With Sandisk’s 10 year warranty they replaced it and sent me a new one at no charge. That is the advantage when you purchase high tech from a top company that stands behind their product. I simply called them and returned the old chip and they sent me a new one. I am amazed at how well these work and how low the price has gotten on a sale day. Putting one of these into your phone or tablet is a wonderful upgrade to the device’s storage capability. Almost no one needs a 128 GIG chip but at sales prices you can’t pass up getting them. This is a great product and it makes your smart devices even more powerful. This is a simple and easy upgrade for your smart devices.

Beware of fake cards. The capacity shown on fake cards can be modified to show a size greater than what it actually is. Ex. A fake 256GB card having only 32GB instead. Some unknowing person could use the card without knowing it was fake and find that the data was corrupted when it got past 32GB or encounter a very very slow transfer rate past a certain point. To check if the card you bought is legit or not use FakeFlashTest (fast) and H2testw (slower but thorough). This will delete the content on your card so backup whatever you have before using it. The speed and pictures I got from my legit 256GB card are attached. Your results may vary. The product code is edited out for product support issues.

Purchased for my Nintendo Switch, works perfectly! I originally thought it didn't work because I kept getting an error on my console when I copied my old SD to the new one using my macbook, but apparently the issue was introduced because I used a macbook due to how their files are stored on their SD format. I switched over to Windows, copy/pasted my data from the old to the new and everything just worked like nothing ever happened. Also, I learned that the Sandisk Ultra is actually faster than the Sandisk Extreme for nintendo switch. this is because the Switch explicitly supports the SDXC-UHS-I. So if you're looking to benefit from the speeds on the UHS-III, you're going to actually lose performance by a 10th of a millisecond. TL;DR: If you're looking for a SD card for the switch, no matter the capacity, this is the highest performing chip available to you.

So I just got the 200GB version in the mail. Due to negative reviews I was very worried about how my mSDcad would turn out. So lets get to the point: It is easy for scammers mess with the cards to make them appear bigger than they actually are. So it is IMPORTANT that once you get your card that you download a software called h2testw. I used it and after about an hour or 2 it reported no errors. Everything checks out for mine regarding that concern. I got this card for my switch that I, at the time of writing this, am still waiting to receive. I may update as time goes on, but so far so good. UPDATE: 1 Got my switch, set it up and began downloading the following games : Zelda - Breath of the wild, Mario Kart 8 Deluxe, and Fortnite. So far the games are downloading without issue, 2 which have completed. The microSD is working as expected. The write speeds could be faster however, but for the price I paid and size it is not so bad for an SD card. I reccommend this over ANY nintendo branded m-SDcards

Excellent card! My 32 gigs of space on my Switch got used up, so I’m on to this 64gig card now. The Ultra is the fastest that the Switch can use. Don’t bother with the Extreme.

Bought this for my Paralenz underwater camera that shoots up to 4K 30fps. My camera manufacturer says 128gb V30 is the required max but this card is rated for a min of 10mb/sec "supposedly" and the write speed is undocumented publicly after contacting Sandisk, with transfer speeds to 100mb/sec. Maybe they won't release write speeds because it performs so well they don't want it competing with their next card thats rated at 160mb/s with V30 min speed?.... just speculation of course! But this card performs flawless... not only in my Galaxy Note 4 phone but also in my camera. Leave it formatted in the default exFat and your good! After much research it appears its only weakness may be in burst abilities for use as internal memory but sustained transfer rates are great!... so much so that 4k @ 60fps video was no problem in testing. I'm also astonished this card works so well in my Note 4, I had a 128gb Sandisk in before and this definitely feels faster. At this point I have the highest recommendations for this card.... you can now store mass amounts of 4K footage.... according to my tests so far, about 10+ Hrs of 4K @ 30 fps! I've found other brands often give similar speeds as compared to Sandisk but fail miserably long term in reliability.... Do you really want 400 GB worth of stuff lost because you wanted to save a few bucks with another brand? Sandisk is the most reliable IMO and it's amazing they remain at the front of the pack. It's not the fastest dog out of the gate that wins, but the one who can make it to the finish line first!

Was a real SanDisk Ultra 64G type 10 and meets the speed ratings. It came preformatted with exFAT and is correct 64G chip, not a fake. Please note that Amazon is throwing all the reviews for all the chips into one place. So if you want accurate reviews, be sure you are looking only at reviews for you particular chip. This review is only for the SanDisk Ultra 64G microSD with SD adapter. I ran a free drive and memory test program on it. It passed 5 complete passes of testing every memory byte in several different test patterns without any failures. This verified capacity and accuracy of read writes over a few hours time. I then ran ATTOs Disk Benchmark tool and it's results show that it does reach very near 100MB/s read speeds and 40Mb/s write speeds. No laptop I have or other device is as fast as my computer's USB 3.1 ports so that seemed to be the best way to test. See the screen capture of the test results attached. Like most SDs or microSDs they do best when working with 64kB or larger transfer sizes. I've found this to be common for 16G SDs all the way up to 400G SDs. That might be a function of the USB port rather than the actual memory. If you are transferring things like small pictures or data files, you probably won't get those speeds. Notice in the chart, small sized transfers are really bad speeds. 64k transfer size is the sweet spot. If you are not using a device that can read and write at the SD card's rated speeds, your tests will likely show the controllers limitations as the top speed. The slowest device in the file transfer chain determines maximum speed. It sustained the transfers for 2GB without problems. These tests were performed with the microSD installed in a Transcend microSD to USB3.0 adapter and that adapter into an available USB3.1 port on my PC. So my top capability will be that of USB3 which is far above what the card speeds could be. You need USB 3.0 or higher to get near the data speeds. USB 2.X or 1.X will not be able to achieve anywhere near those speeds because the USB will bottleneck the data as the cards are faster than the port. Most older SD card readers on devices also won't attain anywhere near that 100MB/s read speed. That's why I test with USB3 instead of a card reader of unknown capabilities. This 64G card will not do 4k video well at all. This card is not designed to. For that you must go to their extreme line of cards with the v30 certification stamp. The reason they don't warrant these in drones or dash cams or DVRs is because these cards were never designed for that kind of constant writing. They will work fine with 1080p video 60FPS or high resolution photo taking. DSLR cameras that snap photos in fast succession by holding down a photo type button also might struggle with this card. Too many people here have said these cards don't meet the speed requirements advertised. I'm telling you that the vast majority of these people have no clue how to test SD speeds and have card readers and testing devices that don't support these speeds. The ad only refers to read speed as 100mB/s, not write speed. The ad doesn't mention the write speed for this card. But on the SanDisk website it says 40MB/s. Most SD cards write speeds are about 40-60% of the read speed if you can't find write specs. That's is why SD cards (and most SSD drives) transfer data out of them (read) faster than they do to transfer data into them (write). If you go to the SanDisk website, (at the date of this review), it showed 100mB/s maximum read speed and 40mB/s maximum write speed in the specs. That's what I verified this card is doing. Also this is an Ultra card, not an Ultra Extreme. Some reviewers have read the specs for the faster card and apply it to this one by mistake of thinking that the slightly different name is the same card. Exact naming and certification stamps and specs other than just the read/write speed are very important when looking at SD cards that can do 4k videos. This Ultra is a type 10 card and is fine for taking photos and HD video up to 1080p 60FPS. It does not have the v30 stamp of approval for 4k video. If you are an owner of any device that does 4k video, don't buy this card. I noticed a huge number of the one and two star reviews were from people who don't understand video, photo, and audio requirements of their device and go to buy a cheaper card and end up disappointed when their device didn't support it. If you are using 4k video devices be sure your memory at least has the v30 stamp or don't buy it for 4k use. If the price of the card is really cheap it's very likely its not top of the line. Do some research by reading your device manual specs 1st. It'll generally tell you exactly what kind of card you need to get. Don't buy any SD memory just because it's cheap. That will almost always get you into trouble. Understand that this 64G microSD Ultra is formatted with exFAT which is now the industry standard for any SD or USB drive over 32G. You can't have a drive bigger than 32G with FAT32 in Windows. Also FAT32 limits you to a maximum of 4G file sizes. Since almost any lengthy HD video will eventually want to go past that, the exFAT format solves that limitation. Some older devices that record video will only make 4G files then start a new file when it reaches that file size. You then have to put them together yourself. If you use some third party formatting programs that don't use Windows to do the format, they can make bigger FAT32 drives. Sometimes they are then not recognizable by programs that do religiously follow the FAT32 is for only 32G and less rule. So if your device can't understand exFAT you'll have to try some of those custom formatter programs or stick to 32G SD/USB cards in your device if it only knows FAT32 formatting. Many card reader devices haven't been modernized to see an exFAT drive. I do like the SanDisk memory a lot. I've never got a bad one. I did once get a fake one a few months ago from Amazon. And so I think it's important to discuss fakes. Apparently from the reviews, lots of people have got fake SanDisks and other brand names from Amazon. When resellers like Amazon buy product from several companies at the thousands of parts level, they don't have time to individually check every one of those for authenticity. Especially considering many of these fakes require hardware testing. These fakes either don't match capacities or die within a short period of time or don't perform anywhere near rated levels. Some could even pop the chip or burn it and the controller up. So it's important to spot fakes as soon as possible. Fakes are also often chips that failed the manufacturer's tests, get bought for scrap by an unscrupulous company who then proceeds to relabel and brand them like a large capacity name brand card in order to earn the extra dollars someone would pay for the larger good SD. Since these fakes can be introduced anywhere along the supply chain, they are difficult to weed out unless every item is checked for authenticity. In some countries where these come from, it's not even illegal. Get some software memory testers or drive programs to test your USB/SD cards. Usually software ones are free or really cheap. Hardware ones will likely cost you $$. If you don't intend on testing a lot of SDs, just get the software testers. Verify the new chip you got was real by checking capacities and set test loops to test every memory byte over and over for at least an hour before dedicating them to your valuable data. Sometimes the chips that fail over a few days or weeks of time were fake ones. But there's a catch to testing too much. SD drives have a limited amount of times they will write to a location. Sure that's usually hundreds of thousands of times. But if you test a lot, you are also doing writes to the card. So don't test for long periods of time as that can wear out your chips future write-ability. Also look closely at the packaging before you tear the package open to remove the card. If the print and colors look off or out of focus or smeared, it's very probably a fake. Sometimes it's obvious sometimes it's not. Look for really poor language translation in labels. Sometimes fakes are downright laughable in spelling errors. If its already an open package, it may be fake. The makers of these fake chips insert them into the supply chain to buyers like Amazon. Then the seller to individual customers (like Amazon) generally has no knowledge they are selling fakes as some are real and some are not. The person who sold it to you is the only one you should attempt a refund from. If you do get a fake one, get a refund or exchange from Amazon. Amazon is legally liable to replace them no matter what they may tell you about the item being not returnable. Don't try to do a SanDisk warranty as they will just tell you, you bought a fake and they are not responsible. (And they aren't...It's usually not their fault). Amazon has a responsibility to you but they may want you to return the card and packaging for their own evaluation proof (rare). Don't just copy some data to the card and call it good. Many fakes are programmed to report the full GB values sold while only having much smaller chips in the microSDc. So lets say you ordered a 64G and really get a fake 2G. The SD might report as 64G but may not format right. Or the first 2G might work fine and then when you go beyond that, it tries to write new info over the top of the 1st 2G of data and corrupts your data. When you see a lot of reviewers say the card worked fine for a week or so and then started to corrupt data, this is usually what's happening. A good memory tester (free software) will check every memory bank with patterns and if any don't pass the tests, it will tell you. You can let them run for a hour or so checking the SDs over and over. Again don't let these tests go on for long periods of time as the testers are writing to memory each pass they make. But you do need to let the testers run long enough to get at least 3 good passes through all the memory. Don't let the fear of getting a bad SD or microSD scare you away from these products. The vast majority of people getting these have received the real deal. Test your cards in the first days after you get them. Past 30 days and you may be on your own. I've used and installed numerous microSD cards and SD cards on all types of equipment. I only once got a fake and it was rather obvious. It's rare to get a fake but something you should be aware of. All the ones I've got from SanDisk perform at the speed they are rated at. So when you see someone say they can't get the speed rating advertised, its 90% of the time their hardware or ignorance of how to test them. SanDisk is one of the better manufacturers of memory devices and yet remains in the middle on pricing. It's hard to go wrong with SanDisk. This particular 64G card I bought this time is being used in a 1080p/60FPS Sony camcorder. It works great for that resolution and frame rate. I also currently have 4 3D printers that I also use nothing but SanDisk in. The crappy no name memory that came with all those printers failed within a month. Some of the SanDisk SD/microSD cards I own have now been in those printers for years without fail and some were in operation in other devices (like Roku's and such). All nonvolatile memory has a limited number of writes that can be done. So after a while they will go bad. The only way to avoid that is to limit how often you write to them. The more often you write to them the less product life you will have. So if you want your cards to last, edit the files on a system with RAM and hard drives and only send to the SD card when the editing is complete. Hope that helps some folks trying to consider whether or not to buy these cards.