One of the questions that we get a lot of on this blog relates to the Difference between SD, SDHC and SDXC cards. It can be very easy to mistake the three cards, simply because they come from the same card family, have the same physical dimensions and even though they are almost the same, they are fundamental differences between the three.
The MAIN DIFFERENCE between SD, SDHC and SDXC cards is really the amount of data that each card format is capable of holding (explained below). You should also be aware that some cards might not be able to work in some devices (See compatibility for each card below).
SD, SDHC and SDXC memory cards physically all have the same shape, look and weight. They all measure 32 mm x 2 4mm x 2.1 mm (which is about the size of a postage stamp). They also weigh 2 g.
SD – Secure Digital Memory Card
SD cards are considered to be old technology. These cards have limited storage capabilities, some of which would be gobbled up by today’s data hungry devices. Even though SD cards are old, they are still popular simply because they are dirt cheap and they can also be used in older devices that use the SD format.
Use: You will find that these cards are ideal for older cameras or other devices that use the SD format. Great cheap storage (1 GB/2 GB sizes) to store data, videos, music, pictures on.
Sizes – SD Cards sizes vary from (smaller sizes 1 MB-32 MB), 64 MB, 128 MB, 256 MB, 512 MB, 1 GB to 2 GB
Speeds – Class 2 (2 MB/s), Class 4 (4 MB/s), Class 6 (6 MB/s) and Class 10 (10 MB/s)
Compatibility – SD cards can be used in devices that can take SD, SDHC and SDXC memory cards.
SDHC – Secure Digital High Capacity Memory Card
SDHC is the popular format out right now. Even though SDXC is newer and the popularity is growing, the popularity of SDHC remains sky high. These cards are capable of handling the data demands of new digital cameras, video cameras and other devices. If you get some of the bigger sized cards (16 GB and 32 GB) they can store HD video and high quality pictures without the fear of them filling up quickly.
Use: Higher capacity cards great for recording HD video. Excellent storage option for your data as card prices are cheap and falling as SDXC popularity increases.
Sizes – SDHC Cards sizes vary from 4 GB, 8 GB, 16 GB to 32 GB
Speeds – Class 2 (2 MB/s), Class 4 (4 MB/s), Class 6 (6 MB/s) and Class 10 (10 MB/s)
Compatibility – SDHC cards can be used in devices that can take SDHC and SDXC memory cards.
SDXC – Secure Digital Extended Capacity Memory Card
The future right now is SDXC. With cameras and video cameras creating higher quality videos and images, more storage space is going to be needed. SDXC is capable of satisfying the demand for data with their phenomenal storage capabilities. Even though they are on the expensive side, these cards are perfect for people or devices that have a need for ample storage space.
Use: You will find that these cards are ideal for older cameras or other devices that use the SD format. Great cheap storage (1 GB/2 GB sizes) to store data, videos, music, pictures on.
Sizes – SDXC Cards sizes vary from 48 GB, 64 GB, 128 GB up to 2 TB
Speeds –Class 10 (10 MB/s) and UHS-1 (up to 312 MB/s)
Compatibility – SDXC cards can be used in devices that can take SDXC memory cards.