When it comes to choosing between SDHC (Secure Digital High Capacity) and SDXC (Secure Digital Extended Capacity) memory cards, there are a few key differences to consider. Both card types use flash memory and are commonly used in digital cameras, camcorders, and other devices. But they have different maximum capacities and uses.
In short, SDHC cards have a maximum capacity of 32GB, while SDXC cards can store up to 2TB. SDHC uses the FAT32 file system, while SDXC uses the exFAT file system. SDXC also supports 4K video recording, while SDHC cards max out at 1080p HD video.
Below we’ll take a deeper look at how SDHC and SDXC compare in terms of compatibility, capacity, speed, durability, and pricing. By the end, you’ll have a clear understanding of which format best fits your needs.
Compatibility
The good news is that both SDHC and SDXC cards are backwards compatible. So an SDHC card will work in a device designed for SD cards, and an SDXC card will work in a device made for SDHC cards. However, it will not work the other way around. Meaning you cannot use an SDXC card in an SDHC-only device, as the device will not be able to recognize the exFAT file system that SDXC uses.
To utilize the extra storage capacity of an SDXC card, your device must specifically support SDXC cards. Most modern consumer cameras and camcorders support both formats, but older models may only work with SDHC. It’s a good idea to double check your device’s manual or specifications to ensure compatibility with SDXC if you want to use the higher capacities.
Capacity
The key difference between SDHC and SDXC comes down to storage capacity.
SDHC stands for “Secure Digital High Capacity” and any SD card between 4GB and 32GB in size is an SDHC card. So if you need an SD card 32GB or smaller, look for one marked SDHC.
SDXC stands for “Secure Digital Extended Capacity” and refers to any SD card 64GB in size or larger, up to a maximum of 2TB. So if you need a card 64GB or larger, an SDXC card is required.
Here is a quick breakdown of the storage capacities:
| SDHC | 4GB – 32GB |
| SDXC | 64GB – 2TB |
As you can see, if you need an SD card larger than 32GB, SDXC is the only option. SDHC maxes out at 32GB. This makes SDXC better suited for high resolution photos and video, as well as applications that require downloading large files onto the card.
Speed Class Ratings
Both SDHC and SDXC cards are available in different speed classes, which indicate the minimum guaranteed sustained write speed. Higher speed classes allow for faster write speeds, which is especially beneficial when shooting bursts of high-res photos or high bitrate video.
Common speed classes include:
| Class 2 | 2 MB/s minimum write speed |
| Class 4 | 4 MB/s minimum |
| Class 6 | 6 MB/s minimum |
| Class 10 | 10 MB/s minimum |
| U1 | 10 MB/s minimum (Ultra High Speed 1) |
| U3 | 30 MB/s minimum (Ultra High Speed 3) |
There are also faster video speed classes specifically for recording high bitrate video:
| V6 | 6 MB/s minimum (Class 6) |
| V10 | 10 MB/s minimum (Class 10) |
| V30 | 30 MB/s minimum (U3) |
| V60 | 60 MB/s minimum |
| V90 | 90 MB/s minimum |
When shopping for either an SDHC or SDXC card, choose one with a speed class rating that matches or exceeds the requirements of your device. This ensures you can take full advantage of the capabilities of your camera or camcorder when recording video or shooting rapid-fire bursts of images.
As a general rule of thumb, Class 10 and U1 cards are suitable for most standard definition cameras. For mid-range to prosumer HD video recording and burst photo shooting, look for U3 or V30 rated cards. V60 or V90 class cards are recommended for professional 4K video recording.
Durability
SD cards have no moving parts, so they are generally quite durable. Both SDHC and SDXC cards use durable flash memory chips encased in a protective shell made of sturdy plastic. However, they can still be damaged by external forces like heat, water, magnets, or impacts.
To make cards more durable for challenging shooting conditions, many manufacturers produce SDHC and SDXC cards rated to withstand:
– Extreme temperatures – Useful for outdoor and adventure photography/videography in cold winter climates or hot desert environments. Look for cards rated -13°F / -25°C or higher for cold weather and 185°F / 85°C or higher for hot weather use.
– Water – For use during ocean, sea or pool water shooting. Opt for cards with waterproof ratings like IPX7 and IPX8, with an underwater depth capacity over 30 meters.
– Shocks/impacts – For active use cases where the card may be dropped, like action cams or drones. Durability ratings to handle 2000G or higher impacts are most robust.
– X-rays – Cards with X-ray proof construction allow them to pass through airport security scanners without damage or data loss.
So in terms of durability, there is no inherent difference between SDHC and SDXC formats. But within both formats, you can find cards built to withstand more abuse than standard cards when shopping carefully.
Pricing
When it comes to cost, SDHC cards tend to be a bit less expensive than SDXC cards at smaller capacities. A 32GB SDHC card costs roughly $5-10, while a 64GB SDXC card of equal speed class runs around $10-15. However, at higher capacities the price difference becomes negligible, and SDXC cards can actually be cheaper per gigabyte than SDHC.
For example, a 256GB SDXC card currently costs roughly $30-$60. To get the same capacity with SDHC cards, you would need eight 32GB SDHC cards, which would cost over $80. So above 64GB, SDXC becomes more affordable.
Here is a rough pricing comparison of SDHC vs SDXC at different capacities for Class 10 U1 rated cards:
| 32GB SDHC | $5 – $10 |
| 64GB SDXC | $10 – $15 |
| 128GB SDXC | $15 – $30 |
| 256GB SDXC | $30 – $60 |
So if you need lots of storage space, an SDXC card provides better value, despite the slightly higher initial cost for cards 64GB and under. The more data you need to store, the more you can save by going with SDXC over multiple smaller SDHC cards.
Which Is Better for You?
Now that you understand the key differences between SDHC and SDXC cards, which is better for you?
Get an SDHC card if:
– You only need up to 32GB capacity
– You have an older device that is not SDXC compatible
– You are on a tight budget and only need up to 32GB
Get an SDXC card if:
– You need 64GB of storage space or higher
– You have a newer camera or camcorder that supports SDXC
– You frequently shoot HD, 4K or burst mode photos/video
– You want the best value for higher capacity storage
If you’re unsure about compatibility, it’s always best to check your device’s manual or specifications to confirm which format it works with.
For most consumers though, SDXC is the better choice if your device supports it. The SDXC format is newer and can store way more data, which comes in handy for higher resolution media files. Plus SDXC cards over 64GB generally offer better value than buying multiple smaller SDHC cards for the same capacity.
Conclusion
SDHC and SDXC cards have several similarities, as they both use high-speed NAND flash memory and come in a range of speed classes for seamless performance. But SDXC pulls ahead when it comes to capacity, supporting vastly higher storage ranging from 64GB up to 2TB. The SDXC format also enables advanced features like 4K video recording. So for most users with compatible devices, SDXC is the superior, more future-proof choice. But SDHC remains a good option for basic needs up to 32GB.
When shopping for either SDHC or SDXC cards, select a reputable brand and aim for the highest speed class rating your device supports. Carefully compare prices to find the best value at your desired capacity. And double check that the card format suits your device’s technical specifications. With a little research, you can find the perfect SDHC or SDXC card to meet your storage needs and budget.
