CFexpress Type A vs Type B: Which Memory Card Is Right for You?

If you're a photographer or videographer shopping for a new memory card, you've likely encountered the CFexpress format. Within this standard, there are two main form factors: Type A and Type B. While they share the same underlying technology, they differ significantly in size, speed, and compatibility. Understanding these differences is crucial to making the right purchase for your camera and workflow.

In this guide, we'll break down the key distinctions between CFexpress Type A and Type B, compare their performance, and help you decide which one is the best fit for your needs. We'll also highlight some compatible products from Glyphtech, such as the Capture+ CFexpress Type B 4.0 Memory Card, to give you a concrete example of what to look for.

What Are CFexpress Cards?

CFexpress is a memory card standard designed to deliver high-speed data transfer for professional photography and video recording. It uses the PCIe interface and NVMe protocol, offering read and write speeds that far exceed traditional SD cards. The CFexpress standard includes three form factors: Type A, Type B, and Type C. Type A and Type B are the most common, with Type C reserved for niche applications.

The main difference between Type A and Type B lies in their physical dimensions and the number of PCIe lanes they use. Type A cards measure 20mm x 28mm x 2.8mm and utilize one PCIe lane, while Type B cards are larger at 38.5mm x 29.6mm x 3.8mm and use two PCIe lanes. This size and lane difference directly impacts their maximum theoretical speeds and the types of devices that can accommodate them.

• Type A: 20mm x 28mm x 2.8mm, one PCIe lane
• Type B: 38.5mm x 29.6mm x 3.8mm, two PCIe lanes

Speed and Performance Comparison

When it comes to speed, Type B has a clear advantage. Because it uses two PCIe lanes, it can achieve much higher data transfer rates. The CFexpress 4.0 standard, for example, allows Type B cards to reach read speeds up to 3400 MB/s and write speeds up to 3000 MB/s. In contrast, Type A cards, with their single lane, typically max out at around 800 MB/s read and 700 MB/s write, even with the newer 4.0 specification.

For most professional workflows, especially those involving high-resolution raw photography or 8K video recording, the extra speed of Type B is invaluable. It allows for faster burst shooting, quicker buffer clearing, and seamless high-bitrate video capture. However, for many users, Type A's speed is more than sufficient, especially if you're shooting stills or 4K video at moderate bitrates.

• Type B: up to 3400 MB/s read (CFexpress 4.0)
• Type A: up to 800 MB/s read (CFexpress 4.0)

Compatibility and Camera Support

One of the most critical factors in choosing between Type A and Type B is your camera's card slot. These form factors are not interchangeable—you cannot use a Type B card in a Type A slot and vice versa. Most mirrorless cameras from Sony, such as the A7 IV and A1, use Type A slots, while many high-end cameras from Canon, Nikon, and Fujifilm use Type B slots. Some cameras even have dual slots that support both formats, but that's rare.

Before purchasing a card, always check your camera's specifications to see which type it supports. If you're unsure, consult the user manual or the manufacturer's website. For example, if you own a camera with a Type B slot, you might consider the Capture+ CFexpress Type B 4.0 Memory Card from Glyphtech, which is designed to deliver high performance for demanding applications.

• Always verify your camera's card slot type before buying
• Type A is common in Sony cameras; Type B is used by Canon, Nikon, Fujifilm

Physical Size and Portability

The physical size difference between Type A and Type B is significant. Type A cards are much smaller, similar in size to an SD card, which makes them ideal for compact camera bodies. This allows manufacturers to keep their cameras smaller and lighter, which is a major selling point for travel and street photographers. Type B cards are larger and require more space, so they are typically found in larger, more professional camera bodies.

If portability is a priority, Type A's smaller footprint is a clear advantage. However, the larger size of Type B cards also means they have more room for flash memory chips, which can contribute to higher capacities in a single card. Currently, Type B cards are available in capacities up to 2TB, while Type A cards typically top out at 1TB, though both are likely to increase over time.

• Type A: compact, similar to SD card size
• Type B: larger, allows for higher capacities

Pricing and Value

Generally, Type A cards are more expensive per gigabyte than Type B cards, despite being slower and having lower capacity. This is partly due to the smaller market and the engineering required to fit high-speed components into a tiny form factor. For budget-conscious buyers, Type B often offers better value if your camera supports it, as you get more speed and capacity for your money.

However, the total cost of ownership includes the card reader. Type A cards often require a dedicated reader, while Type B readers are more common and sometimes double as XQD readers. If you're starting from scratch, factor in the cost of a compatible reader. Some products, like the Connect+ High-Performance USB4 80Gbps/240W Type-C Cable, can ensure fast data transfer from your card reader to your computer, maximizing your workflow efficiency.

• Type A is typically more expensive per GB
• Consider the cost of a card reader when budgeting

Use Cases and Recommendations

So, which should you choose? If you own a camera with a Type A slot, such as many Sony models, your decision is straightforward: you need Type A cards. They offer excellent performance for most photography and 4K video work, and their compact size is a plus. For users with Type B slots, Type B cards are the obvious choice, providing top-tier speed for demanding applications like 8K video and high-speed burst photography.

For professionals who need the absolute best performance, Type B is the way to go. The Capture+ CFexpress Type B 4.0 Memory Card is an excellent example of a high-performance Type B card that can handle the most intensive tasks. On the other hand, if you prioritize portability and your camera is compatible, Type A cards are a solid choice that won't disappoint.

• Type A: ideal for Sony camera users and those who value compactness
• Type B: best for high-end photography and 8K video recording

In the end, the choice between CFexpress Type A and Type B comes down to your camera's compatibility and your specific needs. Both formats offer excellent performance, but Type B has the edge in speed and capacity, while Type A excels in portability. Whichever you choose, ensure you invest in a high-quality card from a reputable brand. For those with Type B slots, the Capture+ CFexpress Type B 4.0 Memory Card from Glyphtech is a reliable option that delivers the speed and reliability you need for professional work.