The extreme resolution of today’s cameras, coupled with their ability to capture high FPS photos and up to 8K video, places huge demands on the speed of memory cards. If you’ve ever had to wait dozens of painful seconds for the buffer to empty, you’ll know what I’m talking about. For this reason, I tested memory cards from different parts of the price spectrum directly in Nikon cameras – including CFExpress, XQD, and SD cards – to show you which ones are the fastest.
Memory card manufacturers know how important speed is, which is why they proudly proclaim the read and write speeds glowing in gold lettering on the box. In an ideal world, these numbers would make for the perfect buying guide. But we live in the real world, where the information written on the box does not always mean very much.
Are manufacturers trying to lie to us? I would like to think not. However, their test conditions are far from the real world. That’s why I decided to find out the practical read and write speeds for myself.
For now, I have tested the 31 memory cards below. I will expand this real-life speed ranking every time I use a new memory card in the future.
How I Tested
I performed the tests below using a Nikon Z9 or Nikon Z8 coupled with a 50mm f/1.8 lens. Both cameras have the same maximum frame rate, the same buffer capacity, and the same file sizes. The advantage of the Z8 is that it also allows you to test SD cards. I set lossless compressed RAW (average file size 54.8MB), 1/1000s, f/2.8, and continuous shooting at the highest rate of 20 FPS. I shot the test scene for 60 seconds. This was repeated for five different test scenes to minimize the measurement error and the effect of the scene on the file size.
To measure read speed, I used my MSI Creator Z16 laptop (Intel Core i9, Geforce RTX 3060, USB3.2 Gen2 ports). For the connection between the card and the laptop, I used Exascend USB 3.2 Gen 2 Dual-Slot Readers (CFExpress B and SD cards) and Lexar Professional XQD 2.0 USB 3.0. For testing I used the EaseUS DiskMark application. Again, I took 5 measurements and then averaged the results.
I did not test the cards’ ability to resist overheating, nor did I measure their speed as a function of temperature. This measurement would certainly be very interesting, but would require strictly standardized conditions, which are not easy to achieve. The original Nikon MC-CF660G CFexpress Type B, the Delkin Devices 325GB BLACK CFexpress Type B or the ProGrade Digital 650GB CFexpress 2.0 Type B Cobalt cards are reported to give very good results in this respect. So, if you plan to use the card primarily for 8K raw video recording, you should consider this feature as well, in addition to speed.
The Results
In the first few seconds of high-FPS shooting, I did not notice any significant differences between the different cards. This is due to the relatively deep buffer of the Nikon Z9 and Z8. However, once the buffer is full, the differences become apparent, as the slowest cards immediately grind to a halt. On the worst card I tested, the frame rate after the first few seconds dropped precipitously, and the average speed over 60 seconds was a mere 1.9 FPS.
With that, let’s get into the tests.
#1 Nikon MC-CF660G CFexpress Type B
Declared write speed: 1500 MB/s
Declared read speed: 1700 MB/s
Average measured write speed: 854.9 MB/s
Average measured frame rate: 15.6 fps
Suitable for 8K video: Yes
Regular price: $726
#2 ProGrade Digital 650GB CFexpress 2.0 Type B Cobalt
Declared write speed: 1500 MB/s
Declared read speed: 1700 MB/s
Average measured write speed: 847.6 MB/s
Average measured frame rate: 15.5 fps
Suitable for 8K video: Yes
Regular price: $540
#3 Delkin Devices 150GB BLACK CFexpress Type B
Declared write speed: 1530 MB/s
Declared read speed: 1725 MB/s
Average measured write speed: 843.9 MB/s
Average measured frame rate: 15.4 fps
Suitable for 8K video: Yes
Regular price: $180
Where to buy: B&H
#4 Delkin Devices 325GB BLACK CFexpress Type B
Declared write speed: 1530 MB/s
Declared read speed: 1725 MB/s
Average measured write speed: 839.9 MB/s
Average measured frame rate: 15.3 fps
Average measured read speed: 1067.0 MB/s
Suitable for 8K video: Yes
Regular price: $425
Where to buy: B&H
#5 Delkin Devices 128GB POWER CFexpress Type B
Declared write speed: 1700 MB/s
Declared read speed: 1780 MB/s
Average measured write speed: 832.4 MB/s
Average measured frame rate: 15.2 fps
Average measured read speed: 1055.6 MB/s
Suitable for 8K video: Yes
Regular price: $110
#6 Delkin Devices 256GB BLACK CFexpress Type B
Declared write speed: 1400 MB/s
Declared read speed: 1645 MB/s
Average measured write speed: 831.0 MB/s
Average measured frame rate: 15.2 fps
Average measured read speed: 821.3 MB/s
Suitable for 8K video: Yes
Regular price: $_ _
Where to buy: No Longer Available
#7 Exascend Essential CFexpress B 1TB
Declared write speed: 1700 MB/s
Declared read speed: 1800 MB/s
Average measured write speed: 805.6 MB/s
Average measured frame rate: 14.8 fps
Average measured read speed: Not measured (to be added)
Suitable for 8K video: Yes
Regular price: $469
#8 ProGrade Digital 325GB CFexpress 2.0 Type B
Declared write speed: 1500 MB/s
Declared read speed: 1700 MB/s
Average measured write speed: 804.3 MB/s
Average measured frame rate: 14.7 fps
Average measured read speed: 1033.2 MB/s
Suitable for 8K video: Yes
Regular price: $450
#9 Delkin Devices 325GB BLACK G4 CFexpress Type B
Declared write speed: 1700 MB/s
Declared read speed: 1800 MB/s
Average measured write speed: 804.3 MB/s
Average measured frame rate: 14.7 fps
Suitable for 8K video: Yes
Regular price: $280
Where to buy: B&H
#10 ProGrade Digital 512GB CFexpress 4.0 Type B Gold
Declared write speed: 2400 MB/s
Declared read speed: 3400 MB/s
Average measured write speed: 762.6 MB/s
Average measured frame rate: 13.9 fps
Suitable for 8K video: Yes
Regular price: $180
Where to buy: B&H
#11 Nextorage 165GB NX-B1PRO Series CFexpress Type B
Declared write speed: 1900 MB/s
Declared read speed: 1950 MB/s
Average measured write speed: 759.3 MB/s
Average measured frame rate: 13.9 fps
Average measured read speed: 1034.7 MB/s
Suitable for 8K video: Yes
Regular price: $170
#12 Wise Advanced 1TB CFX-B Series Mark II CFexpress Type B
Declared write speed: 1550 MB/s
Declared read speed: 1700 MB/s
Average measured write speed: 748.9 MB/s
Average measured frame rate: 13.7 fps
Average measured read speed: 600.8 MB/s
Suitable for 8K video: Yes
Regular price: $400
Where to buy: B&H.
#13 Delkin Devices 128GB POWER G4 CFexpress Type B
Declared write speed: 1700 MB/s
Declared read speed: 1780 MB/s
Average measured write speed: 719.4 MB/s
Average measured frame rate: 13.1 fps
Suitable for 8K video: Yes
Regular price: $110
#14 Wise Advanced 512GB CFX-B Series Mark II CFexpress Type B
Declared write speed: 1550 MB/s
Declared read speed: 1700 MB/s
Average measured write speed: 619.2 MB/s
Average measured frame rate: 11.3 fps
Average measured read speed: 603.2 MB/s
Suitable for 8K video: Yes
Regular price: $200
Where to buy: B&H.
#15 Nextorage 512GB NX-B2SE Series CFexpress Type B
Declared write speed: 1900 MB/s
Declared read speed: 1950 MB/s
Average measured write speed: 581.5 MB/s
Average measured frame rate: 10.6 fps
Average measured read speed: 1034.2 MB/s
Suitable for 8K video: Yes
Regular price: $175
Where to buy: Adorama and Amazon.
#16 Lexar 256GB Professional CFexpress Type B Card SILVER Series
Declared write speed: 1300 MB/s
Declared read speed: 1750 MB/s
Average measured write speed: 511.8 MB/s
Average measured frame rate: 9.3 fps
Suitable for 8K video: Yes
Regular price: $140
#17 SanDisk 128GB Extreme PRO CFexpress Type B
Declared write speed: 1200 MB/s
Declared read speed: 1700 MB/s
Average measured write speed: 427.6 MB/s
Average measured frame rate: 7.8 fps
Average measured read speed: 1064.2 MB/s
Suitable for 8K video: No
Regular price: $110
Declared write speed: 400 MB/s
Declared read speed: 440 MB/s
Average measured write speed: 355.1 MB/s
Average measured frame rate: 6.5 fps
Average measured read speed: 355.5 MB/s
Suitable for 8K video: No
Regular price: $90
Declared write speed: 400 MB/s
Declared read speed: 440 MB/s
Average measured write speed: 352.7 MB/s
Average measured frame rate: 6.4 fps
Average measured read speed: 402 MB/s
Suitable for 8K video: No
Regular price: $160
Where to buy: Amazon.
#20 Lexar XQD 32GB 2933x Professional
Declared write speed: 400 MB/s
Declared read speed: 440 MB/s
Average measured write speed: 351.1 MB/s
Average measured frame rate: 6.4 fps
Average measured read speed: 361.3 MB/s
Suitable for 8K video: No
Regular price: $_ _
Where to buy: No Longer Available
#21 Delkin Devices 256GB POWER CFexpress Type B
Declared write speed: 1700 MB/s
Declared read speed: 1780 MB/s
Average measured write speed: 351.0 MB/s
Average measured frame rate: 6.4 fps
Average measured read speed: 473.9 MB/s
Suitable for 8K video: Yes
Regular price: $135
Where to buy: B&H.
#22 Nextorage 128GB NX-F2PRO Series UHS-II SDXC
Declared write speed: 299 MB/s
Declared read speed: 300 MB/s
Average measured write speed: 252.1 MB/s
Average measured frame rate: 4.6 fps
Suitable for 8K video: No
Regular price: $110
#23 ProGrade Digital 256GB UHS-II SDXC
Declared write speed: 250 MB/s
Declared read speed: 300 MB/s
Average measured write speed: 242.3 MB/s
Average measured frame rate: 4.4 fps
Suitable for 8K video: No
Regular price: $202.5
Where to buy: B&H
#24 ProGrade Digital 128GB UHS-II SDXC
Declared write speed: 250 MB/s
Declared read speed: 300 MB/s
Average measured write speed: 239.3 MB/s
Average measured frame rate: 4.4 fps
Suitable for 8K video: No
Regular price: $109
#25 Sony 64GB SF-G TOUGH Series UHS-II SDXC
Declared write speed: 299 MB/s
Declared read speed: 300 MB/s
Average measured write speed: 236.4 MB/s
Average measured frame rate: 4.3 fps
Average measured read speed: 94.3 MB/s
Suitable for 8K video: No
Regular price: $100
#26 SanDisk 64GB Extreme PRO UHS-II SDXC
Declared write speed: 260 MB/s
Declared read speed: 300 MB/s
Average measured write speed: 222.5 MB/s
Average measured frame rate: 4.1 fps
Average measured read speed: 94.5 MB/s
Suitable for 8K video: No
Regular price: $65
#27 ProGrade Digital 128GB CFexpress 2.0 Type B Gold
Declared write speed: 1400 MB/s
Declared read speed: 1700 MB/s
Average measured write speed: 202.5 MB/s
Average measured frame rate: 3.7 fps
Suitable for 8K video: No
Regular price: $100
#28 OWC 128GB Atlas Pro CFexpress Type B
Declared write speed: 1400 MB/s
Declared read speed: 1700 MB/s
Average measured write speed: 198.5 MB/s
Average measured frame rate: 3.6 fps
Suitable for 8K video: No
Regular price: $_ _
Where to buy: No Longer Available
#29 SanDisk 64GB Extreme PRO SDXC UHS-I (95MB/s)
Declared write speed: 90 MB/s
Declared read speed: 95 MB/s
Average measured write speed: 108.1 MB/s
Average measured frame rate: 2.0 fps
Suitable for 8K video: No
Regular price: $34.5
Where to buy: Amazon.
#30 SanDisk 64GB Extreme PRO UHS-I SDXC
Declared write speed: 90 MB/s
Declared read speed: 200 MB/s
Average measured write speed: 106.5 MB/s
Average measured frame rate: 1.9 fps
Average measured read speed: 95.6 MB/s
Suitable for 8K video: No
Regular price: $13.49
#31 SanDisk 32GB Extreme PRO SDXC UHS-I (95MB/s)
Declared write speed: 90 MB/s
Declared read speed: 95 MB/s
Average measured write speed: 102.3 MB/s
Average measured frame rate: 1.9 fps
Suitable for 8K video: No
Regular price: $16
Where to buy: Amazon.
Analysis
What stood out to me was the dramatic difference between CFExpress Type B, XQD, and SD cards. Indeed, CFExpress Type B cards are the speed champions compared to the other card types. At the same time, it turns out that even in this category, it pays to choose carefully. While the best of the cards tested averaged around 15 FPS at 60 seconds of high-speed shooting, there were a few outliers whose speed was shockingly slow.
The speed of a pair of OWC 128GB Atlas Pro CFexpress Type B and ProGrade Digital 128GB CFexpress 2.0 Type B Gold cards (around 3.7 FPS) was far behind the XQD cards and even all SDXC UHS-II cards. For a similar price, you can buy, for example, the more than four times faster Delkin Devices 128GB POWER CFexpress Type B. And believe me, you can really feel the speed difference. The SanDisk 128GB Extreme PRO CFexpress Type B card was also far behind expectations with a speed of 7.8 FPS.
I was also surprised by the inconsistency of card speeds within a single model series. While the aforementioned Delkin Devices 128GB POWER CFexpress Type B (previous generation) was one of the absolute top performers, its 256GB sibling was a complete flop in the test. This particular card also failed me for good when I was shooting in Ecuador. So, as in life, I recommend not putting all your eggs in one basket.
A very interesting result was achieved by potentially the fastest card in the test, the ProGrade Digital 512GB CFexpress 4.0 Type B Gold. It is the only one in the test that already runs on the new CFexpress 4.0 standard. Unfortunately, none of the cameras on the market today can take advantage of the blazing speeds it promises because they lack CFexpress 4.0 support. Its result of 13.9 FPS on the Nikon Z9 is actually below average among similar cards (ranking 10th place among the cards tested here). However, the price/performance ratio is very good, and with a compatible reader, you get a future-proof card that allows you to enjoy fast transfer speeds today.
Taking price into account, I was also impressed by the Exascend Essential CFexpress B 1TB card. This card has a huge capacity and a frame rate of 14.8 FPS, which is almost at the level of the winner of the test. All this for a price of $469, which is among the best price/capacity ratio of all cards tested.
The XQD cards hovered around 6.4 FPS. However, I would not recommend buying them today due to the unfavorable price/performance ratio. The only reason to buy them is if you have a camera that does not support CFExpress Type B cards, such as the Nikon D4. The UHS-II SD cards were about 4.2 FPS, while the UHS-I card I tested achieved a mere 1.9 FPS. However, UHS-I cards can be purchased very cheaply, so if speed is not a priority, this may be the way to go.
As the range of cards used in Nikon cameras has expanded with the Zf to include microSD, I’ll be expanding our test to include them soon. Let me know what cards you would like me to test next!
I use Lexar Gold CFExpress 128GB cards in my Z6ii and Z8 and they perform very well. Their bigger cards, 1 TB and 2TB, are apparently even faster but as said, don’t put all your eggs in one basket.
Which cards overheat the fastest.
I wonder if some cards/cameras are less “choppy” than others. When I hit buffer with a Kingston Canvas React Plus 128GB UHS-II card in my Canon R7 body, I might get 12 shots, then half a second of lock-up, then 22 shots, then three seconds (!) of lock-up, etc. It would be much nicer to have one shot every 1/3rd of a second. Of course, I could configure the camera to shoot at a slower frame rate, but I don’t have time to make that change when I’m shooting a bird and suddenly hitting buffer.
(That said, it’s a bit less choppy with the mechanical shutter.)
No Sony Tough card tests? That’s what I use and I get amazingly fast write/read speeds and they’re actually tough like the name implies! I’ve accidentally sent one through the washer and dryer test, left one in my jeans, lol. I’ve dropped them on concrete and not even a chip or mark. The older Sony XQD cards did chip or break though, I had one or two that still worked but had black plastic missing from the top near the connections/contacts end.
However since switching to Sony Tough 248GB CFexpress Type B cards, I’ve had no issues. Though I never have had any issues with Sony cards as far as losing files or anything like that. I’ve been using their XQD cards since day one in 2012 or so with the D4/D4Ss/D5 and now D6’s. I’m a photojournalist and I’m often covering wildfires and all storms, anything news related, plus I shoot sports and pretty much everything else.
So I know for a fact how strong these Tough cards are. I’ve even had them in freezing temperatures and they survived being submerged in water like I said for an hour and then the hot dryer. Anyways I wish they were included, and I know they’re not the #1 for actual sustained speeds but they’re an excellent compromise on speed for build quality and are very fast too! Pricey, but worth it! I highly, highly recommend them for anyone who greatly values their images and can’t afford to lose all your files. You never know when a card can break or fail, so I trust Sony Tough cards with my career!
I have both of the Delkin Black 325GB cards that you tested. The G4 labelled one at #9 has a Maximum Declared write speed: 1800 MB/s and Maximum Declared read speed: 1700 MB/s. The other at #4 is marginally slower in spec. Yet your tests show the earlier to be faster. Both are fast cards, but the results seem reversed and surprising.
I agree with you Peter that I was surprised by the results of some of the cards. With both the Delkin Black and the Delkin Power, I found the previous generation to be faster. I can’t explain what’s behind that.
SanDisk 128 GB CFE-B is significantly slower than 512 GB version. Both are rather hot though.
This is a difficult topic to get right. There are so many cards. I have a couple of the cards you tested. They perform well as you state. The large Delkin Power card G4 650 Gb is a good card as far as I can tell on the Z9. Apparently size an G number matter so Delkin is confusing. The 512 Delkin Power is slow by comparison with the 650 G4.
Unfortunately what a tester would need to do is pretty much test everything. Which of course is very difficult if not impossible.
The truth is we don’t need opal our cards to be fast. I have several Lexar 64 XQD cards and these are fine in the Z6ii. I plan to keep using them. I have bought different cards for slightly different roles.
I wonder how different the G4 cards are compared with G3.
The “G4” in Delkin’s name is a bit misleading. A buyer might think that he is buying a card of the new CFexpress 4.0 standard, but this is not the case. There is only one such card in the test, and although its performance is high, it falls far behind the claimed specifications. The reason for this is not the card, but the camera. None of today’s cameras can take advantage of 4.0 speeds. If we leave aside the transfer speed, buying a 4.0 card is more of an investment in the future. I agree that it is good to have multiple cards for different purposes. Card speed is a parameter that only a small percentage of photographers (but most videographers) will appreciate.
I bought the 650 Gb (which the computer says is just over 1TB) because I wanted a large card. Tests suggested it is a reasonably quick card.
I have 2 DelkinPower128Gb which tests very well. The 150 Delkin is also quick according to tests. I bought a Power 512 for capacity rather than speed, knowing it had tested as relatively slow (probably why they discounted it to clear stock).
I know that SSD tests are misleading because the bus inside the cameras restrict data flow. We await updated camera bodies with faster data via additional data channels in the future.
What is the difference between the number 5 and 13?
#13 is a G4 version, whereas #5 is not. The thumbnail on #5 should be changed.
Thanks for the heads up, I already did.
#5 Delkin Devices 128GB POWER CFexpress Type B
According to Amazon:
• Item model number DCFX1-128
• Date First Available 7 Nov. 2019
According to B&H: No Longer Available
[https://www.bhphotovideo.com/c/product/1511697-REG/delkin_devices_dcfx1_128_128gb_cfexpress_memory_card.html?fromDisList=y]
The B&H link given under #5 redirects to the newer card, #13.
#13 Delkin Devices 128GB POWER G4 CFexpress Type B
According to Amazon:
• Item model number DCFXBP128G4
• Date First Available 5 Jun. 2023
According to B&H:
• MFR #DCFXBP128G4
• Read Speed Maximum: 1780 MB/s
• Write Speed Maximum: 1700 MB/s
• Write Speed Sustained: 805 MB/s
According to Delkin, as of 2024‑03‑12, this is the current model number, DCFXBP128G4.
Sustained Write Speeds
• 128GB – 512GB: 805 MB/s
• 650GB – 2TB: 1490 MB/s
[https://www.delkindevices.com/cfexpress-type-b-g4/]
While I appreciate the effort behind all of these tests, a few questions remain unanswered namely, 1) You measured performance rates from a card reader connected to a laptop. How is that validated compared to the performance of the card in camera? 2) You referred to FPS of the individual cards, (presuming once the buffer is filled or is that native performance) or how did you calculate that? When did the buffer fill for the individual cards? 3) Temperature is important. 4) Video performance is important.
Hi Mike
If you read the “how i testing” you’ll know that all calculation is software based , if you calculate once buffer is full , will not give you the speed of the card but merely the speed of how fast the hardware in camera can handle the information ? So it will maybe change from camera to camera model/brand
I`m using delkin black cards and very satisfied with that
As for reading speed, I measured the results on a specific combination of card, reader, and laptop. The different readers didn’t make much of a difference. I would expect a difference in read speed for CFexpress 4.0 cards with compatible readers, but those are still very limited.
I think I have sufficiently described the in-camera speed measurement in the article. There are of course other ways to test, I chose to present the results based on 60 second bursts. For some people it might be interesting to know, for example, how long it takes for the buffer to fill, or what the temperature of the card is after the burst, etc. But these are parameters that are hard to measure and are also subject to a lot of environmental influences. Even my test design is not completely bulletproof because I don’t standardize the input temperature of the camera and card. I strongly suspect that it is the temperature of the card that significantly affects its performance.
I’m perfectly happy with my two Prograde Gold 512 gb 4.0 cards delivered today with their fastest card reader all for $365 from Prograde. They are plenty fast for me and someday Nikon will upgrade the software.
These cards are great and are certainly at the top of the pack. In a future camera that can use their speed they will be unstoppable. I wish your new cards fill up not only quickly, but also with great photos. Have a good light, Mark.