Best CFExpress Type-B Memory Cards – 44 Tested

CFexpress Type-B memory cards are larger format memory cards that have become the standard for high-end cameras (except Sony).

The CFexpress Type-B interface differs from CFexpress Type-A cards in that a dual-lane bus is used instead of a single-lane bus. If a device can take advantage of this, you should essentially see double the speed of what Type-A cards can produce.

A new CF4.0 interface was introduced in 2024, and now CFexpress Type-B cards are being released with theoretical read and write speeds of 3,000-3600 MB/s. These are the fastest Cfexpress Type-B memory cards you can buy today.

Do you need the newest CF4.0 cards? Not yet. No camera is taking advantage of this new interface; most cameras only use Type-B cards in the single-lane mode.

CFexpress Type B Memory Benchmarks

Because of the latest CF4.0 technology, many of the older CF2.0 cards have been discontinued. I’ve been trying to benchmark all the latest CF4.0 cards that I can get my hands on. However, many hardware/motherboards or readers still struggle with this new format. Hence, we are in a transitional period as we wait for this technology to mature across all types of hardware.

Software used: AJA System Test for Windows 11. The resolution is 5120×2700 5k Red. The test File Size is 4GB. The codec Type is 16bit RGBA, Single File.

Readers Used: AngelBird 20Gbps USB 3.2 gen 2×2 & Prograde CF4.0 40Gbps CFexpress Type-B card readers.

I’m still struggling with hardware and finding a motherboard with the proper CF4.0 read and write speeds. I can get fast read speeds, but then I have to switch over to the USB3.2 2×2 to get good write speeds. I’ll switch to a new Mac soon and see if that solves the problem. Then, I’ll start collecting more CF4.0 cards to get the real benchmarks, which will be insanely expensive.

Click the plus button to see rated read and write speeds and rated sustained speeds. Not all brands of cards advertise their rated sustained speeds, although they should all write them on their cards as Prograde now does since that’s the only spec that matters for videography.

Best CFexpress Type-B Memory Cards For 8k Video

CFexpress Type B Memory cards can use a TLC, MLC, or 3D NAND flash but can use an SLC cache; this is why, when testing cards, you will see very fast performances, followed by a significant speed drop. What’s happening here is the fast SLC cache has been exhausted, and now the card writes directly to the slower (storage) flash.

If you’re shooting high-end video, it’s important to make sure you have a card with a fast sustain speed rather than a fast general speed, which is generally what is written on the card’s label. The column above shows read and write speeds, as well as the rated read and write and sustain speeds.

A little tricky thing about CF4.0 is that the new interface does not improve sustain speeds over CF2.0 cards since often the bottleneck with sustain speeds comes from the type of flash used. With CF4.0, you’ll see huge improvements to the SLC cache because the SLC cache is very fast, but the 3D NAND, or MLC flash, might only be capable of recording at 400MB/s, more or less.

Finding The Best CFexpress Type-B Memory Card For Your Use Case

Everyone’s use case is different, but if you’re looking for the best CFexpress Type-B memory card for your use case, there are a few things you should pay attention to.

VPG Rating: Not all cards have the VPG rating, and they don’t always need it.

What does VPG mean? It stands for Video Performance Guarantee. This is the guaranteed sustain speed, similar to the V30, V60, or V90 found in SD memory cards. Generally, the slower flash used on the card is capable of sustaining these speeds even after the fast SLC cache has been exhausted.

If you’re a videographer, a VPG-400 rating guarantees the card produces a sustained speed of 400MB/s, which is very important when writing with heavy codecs.

Warranty: You’ll also want to pay attention to the warranty. CFexpress Type-B cards often have thermal compounds, like thermal paste, that connect the memory controller to the card’s housing, allowing it to distribute heat away from the sensitive chip.

Over time, these thermal compounds can degrade and lose their ability to transfer heat. This will cause your memory controller to get too hot, forcing thermal throttling, which then lowers performance.

Often, a good card is rated for only about 5 years. Having a 5 to 10-year warranty will ensure your investment is protected under warranty.

Also, some brands offer a 48-hour replacement program, and some come with drive recovery software.

Top 3 Best CFExpress Cards – The All-Around Best Brands For 2025

If your buying a CFExpress card today, you don’t need to get CF4.0 yet. CF2.0 cards are a little harder to find, but you can still get them on Amazon.

After benchmarking all the different cards in all the cameras, I found that a few brands have stood out as being better than others.

My top picks for brands would be Lexar, Delkin or Prograde. These I think are the best companies right now for premium cards.

There are some great budget options as well, like Pergear or Hoodman Steel. Also I like use Wise and Angelbird cards often, as mid to high end cards.

Sandisk has a Pro Cine card, but it’s still not great. Although Sandisk has always been a trusted brand, its CFexpress cards are still underperforming.

The Sony Tough card still has a very small cache, so they are still not my favorite.

Best CFexpress Type-B Memory Card Reader

CFexpress Type B cards can be very fast with USB 3.2 2×2 readers, which run at 20Gbps, or Thunderbolt 3, which also runs at 20Gbps.

New CF4.0 readers run at 40Mbps, but they require a computer with Thunderbolt 4 or USB4.

Mac Users: Mac Computers, including the new M2 Pro and M2 Ultra machines, do not support USB 3.2 2×2. Even the new computers that use USB4 are only backward compatible with USB 3.2 10Gbps, but they can use Thunderbolt 3 or 4 at 20Gbps if you get a Thunderbolt-specific reader.

Windows x86 Users: PCs can be found with motherboards that support USB 3.2 2×2 and Thunderbolt4/USB-C 4.0. Look for this rating on your motherboard if you buy or build a new PC to make sure it supports USB4.0 or Thunderbolt 4. This will allow you to use the CF4.0 readers, maybe. My Asrock motherboard doesn’t seem to be fully compatible with USB 4.0 yet, even though the marketing material says otherwise. For example I can get the USB4 read speeds but not the write speeds.

Many cameras now offer CFexpress Type B + UHS-II, so having a reader that supports both formats can be very useful, but generally, they are limited to 10Gbps. This is actually what I use for day-to-day shooting. I don’t mind waiting an extra few minutes for my files to transfer at the end of the day when I’m done shooting.

See the Best CFexpress Type B Memory Card Readers for more information.

USB-C CFexpress Type-B Readers

These are the readers I have and use. They all work great. Some can be slightly faster than others depending on what card is used, but for the most part, they are all very close in speed.

Prograde UHS-II + CFxB Reader – Amazon / B&H – I mostly use this for personal use.

The Prograde readers support the faster Sandisk interface, so many UHS-I cards now run properly at the 170MB/s read speeds. It has a magnetic base, which is very useful. This is ultimately why this is my #1 reader. I love sticking it to the side of my computer or metal on my desk.

Lexar CFxB + USB-C Reader – Amazon / B&H

If you can’t fully take advantage of a USB 3.2 setup or need UHS-II, the Prograde UHS-II + Cfexpress reader is only slightly slower; most would never notice the difference.

Key Takeaways

Now that the CFxB space has matured, there are many great card options at various prices. You don’t always need the fastest CFexpress card, and you can save a lot of money by buying a card with only the specs you need. You’ll want to focus on sustain speeds if you’re a videographer.

Keep an eye on thermal throttling with the higher-end cameras and cards, as that will be a better benchmark to look at compared to RAW speed if shooting video is the primary use of the camera.