Without an SD card to record your images, your photographic camera will end up feeling sort of a pricey paperweight. Because an SD card serves as the memory center for your camera, its performance and reliability, in addition to a reasonable price, are key to finding one you can count on. Through our research and testing, we’ve found that the 64 GB SanDisk Extreme Pro is fast enough for a 4K video enthusiast, speedy enough for an impatient downloader, and reliable enough for anyone to use for years to come.
Previous generations of the SanDisk Extreme Pro have pop out on top in our past testing, and therefore the most up-to-date version of this model isn’t any different. This SD card’s quick read speeds minimize the time it takes to transfer photos and videos from the card to a computer, and the Extreme Pro’s equally fast write speeds ensure that images are captured quickly (especially when you’re shooting in burst mode). SanDisk, a subsidiary of Western Digital, remains a particularly reliable source in the narrowing field of external storage manufacturing and guarantees the Extreme Pro with a limited lifetime warranty. You should keep an eye out for counterfeit SD cards, which are still found at some retailers.
If the SanDisk Extreme Pro is out of stock, we advise the SanDisk Extreme. Past versions of the Extreme couldn’t match the Extreme Pro’s performance, but in this year’s round of testing the most recent version had read speeds comparable to those of our pick, and its write speeds were slower than the Extreme Pro’s but still competitive with those of pricier cards from other brands. When you’re shopping, ensure you’re buying the latest generation of the SanDisk Extreme with a 150 MB/s rating, instead of the previous generation, which is rated at 90 MB/s. This card comes with a similar SanDisk lifetime limited warranty, and you’ll typically find it for some dollars less than the extreme Pro.
If you have needs verging on those of a professional photographer, if you use your camera to record a lot of 4K footage, or if you rely on burst mode and end up with full SD cards at the end of a full day of shooting, upgrading to a UHS-II SD card could be well worth the investment. The Lexar Professional 2000x gives blazingly fast read and write speeds and is capped by a lifetime warranty, yet it costs less than many other UHS-II cards.
How we picked
The most important highlights of an SD card are speed, reliability, price, and guarantee.
SD cards are most commonly used in cameras for storing images and video files as you shoot them. Because most cameras can take photos faster than they can write them to the storage, cameras first save images to a small but speedy buffer. Once the buffer is full, the camera must write the pictures to the SD card before you’ll shoot any more. The faster the camera can write data to the card—the card’s write speed—the faster this buffer clears and the sooner you can shoot more photos. So write speed is that the most significant spec for SD cards that you simply use in cameras.
If you use burst mode a lot, it’s important to know how fast a card needs to be to keep up with your continuous raw shooting. We did some back-of-the-napkin math to find out, multiplying the burst frames per second of nuttertool’s camera recommendations in that regard by their average raw-image size to figure out image bit rate in mb per second.
Our mirrorless camera upgrade pick, the Fujifilm X-T3, has a burst-shooting image bit rate of about 638 MB/s, which slows after 36 shots until the camera’s processor clears the images to the SD card. Our point-and-shoot recommendation, the Panasonic Lumix DMC-LX10, isn’t nearly as demanding: It has an image bit rate of about 100 MB/s. Bit rate varies by the camera, generally getting faster as cameras get better. Since an SD card can last you a decade, it’s worth spending the extra $10 now to ensure you aren’t stuck with a slow card.
Read speed is important when you’re copying data from the card to a computer and when you’re reviewing photos on the camera. Read speed isn’t as important for cameras as write speed, but because read speed is usually faster, manufacturers prefer to brag about it on the label. Read speed is more useful for SD cards used for expanded storage in, say, a laptop since in that case you’re mostly accessing media you’ve already put on the card or copying photos from the card to the laptop’s storage. There isn’t much of a difference in reading speeds among the best SD cards, though: All of the UHS-I cards we tested for this update had an average read speed of around 93 MB/s.
This is what you should look for in an SD card:
- Class 10 rating: This rating guarantees the card has a minimum sustained sequential write speed of least 10 MB/s—the bare minimum for shooting 1080p video. (The other speed classes are 2, 4, and 6, which also denote the minimum write speed in megabytes per second.)
- U3 rating: As most cards now have speeds faster than 10 MB/s, Ultra High-Speed classes further change their performance. U3 is lacked for 4K video and assigns a minimum write speed of 30 MB/s. Unless your device shoots only 1080p video, it’s worth confirming that a card has a U3 rating, which gives you the option to shoot 4K.
- UHS-I bus mode: Bus mode may be a standard that dictates how different generations of SD cards work. All the point-and-shoot cameras we recommend supporting a minimum of UHS-I bus cards. The standard is backward-compatible, meaning you’ll use a faster UHS-II card with a UHS-I camera, or a UHS-I card with a UHS-II camera. But you don’t get the full speed of UHS-II unless both camera and card support UHS-II, because it requires an additional row of physical pins to achieve its extra speed.
- 64 GB capacity: A 64 GB SD card should be spacious enough for many uses, and such cards are less costly per gigabyte than 32 GB cards. If you need more room to store your media, many 128 GB SD cards cost about the same per gigabyte as their 64 GB counterparts. Check your device to verify it supports SDXC (extended capacity) cards (meaning cards 64 GB and higher) before buying one. If not, stick to 32 GB to make sure that your card works along with your device.
- Reliability: An SD card holds the only copy of a photo between the time you take it and when you copy it to a computer for editing, so it’s important to get a reliable car from a reputable manufacturer—such as SanDisk, Transcend, or Lexar—to minimize the probabilities of something going wrong. Many SD cards go with a lifetime or 10-year warranty, and also the SD Card Association says most SD cards have a lifespan of about 10 years with “normal usage.”
- Video Speed Class: The V6, V10, V30, V60, and V90 ratings guarantee minimum levels of performance for recording video and indicate the write speeds, in MB/s, for video. Most cards now have their Video Speed Class rating added on the label. The SD cards we tested ranged from V30 to V90.
In 2020, we researched 20 SD card models that met the above criteria and chose models that were new or were updates of any of the five models we tested in 2017. This group included newer generations from brands like Lexar, Transcend, and SanDisk. We found five updated UHS-I models worth testing: the 64 GB SanDisk Extreme Pro, a new generation of the 64 GB SanDisk Extreme, and 64 GB SanDisk Ultra, the 64 GB Transcend High Speed, and the 64 GB Lexar Professional 633x. We also tested three UHS-II models: the 64 GB SanDisk Extreme Pro UHS-II, the 64 GB Lexar Professional 2000x, and therefore the 64 GB Transcend 700S.
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How we tested
We tested the in-camera burst-shooting performance of these SD cards in a full-frame mirrorless camera, the Sony α7 III.
We then plugged each card into a Verbatim USB-C Pocket Card Reader and ran CrystalDiskMark, a benchmarking program designed to test sequential and random read and write speeds on solid-state storage. Among each test, we cleaned the cards and reformatted them using the suggested utility from the SD Association to maintain performance.
The Verbatim USB-C Pocket Card Reader can support the speeds of UHS-II SD cards and is our pick for high-speed card readers. We needed to ensure consistency in our testing of both UHS-I and UHS-II cards to paint a clear picture of how the UHS-II rating increases read and write times.
These are the same methods we’ve used to test SD cards for the past six years, but the cameras, card reader, and laptop we used during our 2020 testing are different from the equipment we used in previous years. This means that although our 2017 test results are still useful, they’re not directly comparable to this year’s benchmarks.
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Our pick: SanDisk Extreme Pro (64 GB)
SanDisk Extreme Pro (64 GB)
The 64 GB SanDisk Extreme Pro proved to be the best SD card in our latest round of testing, with the most effective ratio of reading and write speeds, as well as high-speed real-world performance during burst shooting. It’s a reasonable option that outperforms most other UHS-I cards, and it’s covered by SanDisk’s limited lifetime warranty.
The SanDisk Extreme Pro is a Class 10, U3, V30 card, with a quoted read speed of 170 MB/s. That makes it fast enough to record 1080p and 4K video. In our CrystalDiskMark read and write tests, it performed at a little over 93 MB/s and 84 MB/s, respectively, easily beating out cards from other manufacturers.
|Model||Read MB/s||Write MB/s|
|Lexar Professional 633x||93.91||76.25|
|SanDisk Extreme Pro||93.78||84.58|
|Transcend High Speed||93.02||67.13|
Write speeds are the most important factor for SD cards, and the increased write speed of higher-end cards allows a photographer to shoot in burst mode, raw, and 4K video with fewer delays in processing time. In our testing, we found that the extreme Pro outperformed comparable cards from Lexar and Transcend, which suggests a camera would be ready to shoot more images in a very shorter amount of your time with the extreme Pro than it’d with any of the other UHS-I cards we tested. The previous generation of this card—our former pick in this guide—was the fastest card we tested then, too. (You can spot the new Extreme Pro by the quoted 170 MB/s rating on the card’s label. The older version now costs more than the new model and is quoted at only 95 MB/s, so we no longer recommend it.)
In our read tests, the Extreme Pro fell in line with other comparable models, which all produced read speeds within 1 MB/s of one another. A faster read speed means less time spent waiting for your photos and video to transfer from your card onto your computer.
We also tested each card’s real-world burst-shooting speed in a full-frame mirrorless camera, the Sony α7 III. For these tests, we recorded the sound of the shutter closing as we shot a burst of raw images. The resulting waveforms offer a visual representation of each card’s speed. The large group of spikes at the beginning of each waveform represents a burst of shots, which fill the camera’s buffer and must be written to the SD card before you can shoot more photos. Each spike after that represents a single shot, and between those spikes, the camera is writing files to the SD card. In short: More, closely bumped spikes mean a more high-speed SD card.
In the Sony α7 III, the SanDisk Extreme Pro had practical write speeds that were nearly just like those of our runner-up, the Sandisk Extreme. SD cards we examined from Lexar and Transcend executed slightly faster during our in-camera tests but didn’t offer notable improvement over the extreme Pro.
This newest generation of the SanDisk Extreme Pro comes in just the 64 GB size or larger and costs approximately a similar price per gigabyte for the 64 GB and 128 GB models.
SD cards are more durable than hard drives because they lack moving parts, and they can survive being bumped around and dropped. Like many SD cards, the SanDisk Extreme Pro is rated to survive up to 72 hours in 1 meter of saltwater or freshwater, can withstand temperatures starting from –13 °F to 185 °F, and is unaffected by airport X-rays. It’s also backed by a lifetime limited warranty, which covers the SD card as long as it isn’t used improperly.
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Runner-up: SanDisk Extreme (64 GB)
SanDisk Extreme (64 GB)
The latest-generation 64 GB SanDisk Extreme may be a great option if the SanDisk Extreme Pro is sold out. This card has the same Class 10, U3, and V30 ratings as the Extreme Pro model, making it a suitable card for shooting photographs as well as capturing 4K video.
The SanDisk Extreme recorded write speeds around 66 MB/s within the CrystalDiskMark test, which made it about 23 percent slower than the acute Pro. Still, with that result, plus its impressive read speeds during testing (nearly identical to those of the Extreme Pro), the Extreme easily outperformed other SD cards from Transcend and Lexar, including previous picks just like the 64 GB Transcend W60MB/s.
As for our in-camera burst-shooting tests, the SanDisk Extreme appeared to match the speed of our pick, capturing 15 shots in approximately five seconds. This result was like the sensible performance of other brands’ UHS-II cards, and it means this card could be worth considering for photographers who frequently use burst shooting but don’t want to spend more on UHS-II cards.
The SanDisk Extreme is usually cheaper than the acute Pro model, at a touch over 25¢ per gigabyte compared with 30¢ for our pick. The 128 GB model is out there for a couple of cents less per gigabyte if you would like the additional storage, but we still recommend the acute Pro card if you’re looking to upgrade. The two are backed by an equivalent SanDisk lifetime limited warranty.
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Upgrade pick: Lexar Professional 2000x (64 GB)
Lexar Professional 2000x (64 GB)
With reading and write speeds that are roughly double those of SanDisk’s Extreme Pro UHS-I card, the Lexar Professional 2000x UHS-II card is worth spending a bit extra for if you own a camera that’s UHS-II compatible or if you only want the extra speed when you’re moving photos to your computer or between devices. In our CrystalDiskMark testing, the Lexar had read accelerates to 244 MB/s and write speeds of 203.5 MB/s. Those speeds ended up being slightly above what we got from the costlier SanDisk Extreme Pro UHS-II, by 6.3 MB/s for reading and three MB/s for write. Although the Lexar card was outpaced in write speed by the less costly Transcend UHS-II model we tested, Lexar’s lifetime warranty outweighs the five-year limited warranty Transcend provides.
We haven’t added UHS-II picks in previous reports of this guide for one reason: Not everyone wants UHS-II. Although the increased write speeds of UHS-II make burst shooting a neater lift for your camera, and its quicker read speeds prevent time when you’re exporting images to your computer, the cost-benefit relationship doesn’t add up for the typical person.
|Model||Read MB/s||Write MB/s|
|Lexar Professional 2000x UHS-II||244.2||203.5|
|SanDisk Extreme Pro UHS-II||237.9||200.5|
|Transcend 700S UHS-II||236.7||229.6|
During our in-camera tests, the Lexar Professional UHS-II card also outperformed its comparable SanDisk and Transcend rivals, with significantly less delay between shots after the camera’s buffer period ran out.
Before buying a UHS-II card, check to verify that your camera is UHS-II compatible and make certain to pair it with a UHS-II compatible card reader just like the Verbatim model we used for testing and recommend. Without the right equipment, a UHS-II card won’t perform any better than its UHS-I counterparts.