How to choose the right memory card

We help you select the right memory card for your digital camera, MP3 player or mobile phone

With video, image and data files becoming larger thanks to better quality media, the importance of making sure you have adequate storage is only going to increase this year and beyond. Portable devices such as digital cameras, mobile phones and portable multimedia players often use removable memory cards to store data, so getting the right one is important.

A common mistake is to not budget for an extra memory card when purchasing a device such as a digital camera or mobile phone. Although some devices don’t offer extra storage via a memory card slot, many do, so it’s important to check this when buying a new device. With a variety of memory cards available on the market, purchasing the right one can be a confusing task. Let’s help you to work out what you need!

What device?

The best starting point is to check whether your device has a memory card slot. Depending on the brand and type of unit, the memory card required can differ (examples include SD, CompactFlash, microSD, miniSD).

If the device doesn’t have a memory card slot then it will often have a large amount of internal storage. For example, the Apple iPhone 3GS is available in 16GB and 32GB variants, and it doesn't have a storage slot. The most common devices that use memory cards are digital cameras, mobile phones and portable media players.

Digital cameras

The most common memory card used by compact digital cameras is an SD (Secure Digital) card. An SD card is about the size of a postage stamp and is used by almost all digital cameras, with the exception of Sony models and most Olympus cameras. The largest capacity SD card available is 4GB, though newer SDHC (Secure Digital High Capacity) cards can be bought. The most popular SDHC cards are 8GB in size, but 16GB and 32GB cards are available; 64GB cards will soon hit the market.

Although SDHC cards have the same form factor as regular SD cards, a number of older devices may experience compatibility issues. Before buying an SDHC card, be sure to check that the device you are using it in supports the SDHC format.

For older Olympus and FujiFilm cameras, you’ll need an xD (Extreme Digital) Picture Card. xD cards have a smaller form factor than SD cards, so they won’t fit in an SD card slot and vice versa. xD cards can theoretically have a capacity of up to 4GB, though there are currently no cards over 2GB available on the market. As xD is a proprietary storage solution, xD cards are generally more expensive than their SD counterparts.

Sony cameras require a Memory Stick, which is another proprietary storage solution. Memory Sticks are available in a number of varieties including Memory Stick PRO, which offers higher storage capacities, Memory Stick Duo and PRO Duo, a smaller form factor version of the card, and Memory Stick PRO-HG, a high speed version of the PRO designed for use in high-definition video cameras. The largest capacity Memory Stick currently available is 16GB, though the maximum theoretical capacity according to Sony is 2TB. Memory Sticks are compatible only with Sony branded products and, like xD cards, are generally more expensive than SD cards.

In digital SLR (Single Lens Reflex) cameras, the most common form of memory card storage is CompactFlash (CF) cards – although SD cards are slowly gaining ground in digital SLR cameras. Many newer digital SLR camera models contain both SD card and CompactFlash slots, while other models may only have an SD card slot. CompactFlash cards are widely regarded as more durable than other, smaller memory cards, hence their use in SLR cameras, which are mainly used by professional photographers. The largest CF card available has a capacity of 64GB.

Mobile phones

microSD, formerly known as TransFlash, is the most common memory card used by mobile phones. It’s a favoured format for mobile phones due to its compact size – it’s not much larger than a fingernail. Currently, the highest capacity microSD card available is 8GB, though this is the SDHC variant. As mentioned in relation to SD cards, any microSD card over 4GB in capacity is microSDHC, and these larger capacity cards may not work with all devices. Generally, Nokia, Samsung, Motorola, LG and BlackBerry mobile phones all use the microSD card format. miniSD cards may be found in some mobile phones, though this is rarely the case with newer models.

For Sony Ericsson phones, removable storage comes in the form of Memory Stick Micro (M2) cards. M2 cards are essentially a smaller sized version of the Memory Stick, and are available in capacities of up to 8GB (though 32GB is the theoretical maximum capacity). Some newer Sony Ericsson phones use microSD cards rather than the proprietary Sony M2 cards.

Video Cameras

SD cards are one of the most popular storage formats for video camcorders. Some video cameras can record video directly onto an SD card. Others will record video to the camcorder's built-in hard disk drive or disc, using the SD card memory to store still images. Like Sony digital cameras and Sony Ericsson mobile phones, Sony handycams use the proprietary Memory Stick format, and some JVC camcorders use microSD cards rather than SD.

Other devices

Many other devices also use memory cards. Portable music and media players may have a memory card slot, often in addition to built-in flash memory or hard disk drives. Depending on the brand of media player, the player may support either SD or microSD cards – though many of the newer players will support the SDHC and microSDHC formats for larger capacity cards.

Portable GPS devices commonly store maps on SD cards. A growing number of GPS devices also include multimedia features such as picture viewers and music players and these files may be stored on SD cards for playback through the GPS unit.

Although PDAs (Personal Digital Assistants) aren’t as popular as they once were, there are still a number of models available on the market. Most of them use SD cards, though some use microSD to keep the unit smaller.

Memory card adapters

An important consideration when using the smaller variants of memory cards is a memory card adapter. For example, when using microSD cards, an adapter allows the microSD card to slot into a regular SD slot. This also means you can use your microSD card in the SD card slots found on many PC and notebook computers – making file transfers easier.


No matter the kind of device you use, be sure to consider the amount of data you will need to store at any one time on the device and purchase a memory card with adequate storage.

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