Best Canon PowerShot SD940 IS SD Memory Card

Best PowerShot SD940 IS SD Memory Card

The Canon SD940 IS needs SD memory cards. The largest capacity SD card that can be used in the SD940 IS is 32GB.

MultiMediaCards (MMC) and MMCplus cards can also be used. However, they are no longer manufactured. If you have one, you can use it. If you don’t have one, don’t buy one, they will be more expensive than an SD card.

SD memory cards described as SDUC or SDXC will not work properly in the SD940 IS. These cards are easy to avoid as they are 64GB or larger in size.

The SDHC format was announced in 2006. All 32GB cards that are currently being produced will have almost identical performance. You cannot go wrong buying the cheapest class 10 name brand card. At the time of writing this, the PNY Elite 32GB SD memory card has the best price.

Listed below are some options to choose between that can be used in the SD940 IS. With any of the cards below, you won’t have to be worried about slow performance or SD card data corruption.

PNY Elite 32GB SD Card
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  • Sequential read speed of up to 100MB/s
  • Class 10, U1 rating delivers speed and performance for full HD photography and HD videography.
  • V10 video speed rating to capture uninterrupted HD video at 1920x1080 format
  • Compatible with point & shoot cameras, DSLR cameras, standard & advanced HD-enabled video cameras, and more
  • Reliable & Durable: Magnet Proof, Shock Proof, Temperature Proof, Waterproof
SanDisk Ultra 32GB SD Card
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  • Quick transfer read speeds up to 90MB/s.
  • Write speeds are not capable of recording 4k video.
  • Class 10 rating for Full HD video (1080p).
  • Waterproof, temperature proof, X-ray Proof, magnet-Proof, and shockproof.
Samsung EVO Plus 32GB SD Card
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  • UHS Speed Class 1 (U1) supports Full HD video and burst shots. 130MB/s transfer speeds1 let you upload footage to your PC in an instant.
  • Built to survive tough conditions and heavy usage, whether you’re at home, outside, or on the go. Backed by 10-year limited warranty.
  • Highly durable with comprehensive 7-proof protection.
  • Backed by a 10 year warranty.

Best SD Cards

Make sure to buy a card from a manufacturer with a strong reputation, particularly Lexar or SanDisk. Avoid buying cards from bargain-priced third-party brands.

Memory card issues, for instance a loss of all of your photographs resulting from file corruption, is much more likely to happen with inexpensive cards. A minuscule amount of savings on cost is not worth the reduction in construction quality.

If you need to save a little money, buy a memory card with a smaller capacity. They should be slightly lower in price and you will not have to be anxious about the SD card failing.

Keep in mind, SD card failures are rare. Over the years, I have only suffered from a couple of cards become corrupted. Age could have played a part, as the SD cards were included with previously owned DSLRs.

Canon SD940 IS SD Card Compatibility

The Canon SD940 IS is only capable of using SD memory cards. There are currently 4 separate specifications of Secure Digital (SD) memory cards. The benefit is that there is a boost in the read/write speeds and maximum capacity with the introduction of every updated standard.

Secure Digital memory card readers are backward compatible. A card reader built into a digital camera that can use SDXC cards will also be able to use SDHC and SD memory cards.

The card reader in the Canon SD940 IS is only compatible with the initial two SD card specs. SDXC or SDUC memory cards won’t function correctly.

  • Secure Digital (SD) - These memory cards have a maximum capacity of 2GB and are compatible with the SD940 IS.
  • Secure Digital High Capacity (SDHC) - The capacity of these memory cards range from 4GB to 32GB and are also compatible with the SD940 IS.
  • Secure Digital eXtended Capacity (SDXC) - The capacity of these memory cards range from 64GB to 2TiB.
  • Secure Digital Ultra Capacity (SDUC) - The capacity of these memory cards range from 4TiB to 128TiB.

Canon SD940 IS Memory Card Full Error

SD Card Contacts

Trying to use a card that has a storage capacity of 64GB or larger in size in the SD940 IS will cause the point and shoot camera to display an error message.

Get an SD card which has a storage capacity of 32GB or smaller to resolve the error.

If you are using a memory card that has a capacity less than 32GB, and it is not working, format the SD memory card in the camera.

Speed, Class, & Capacity

SD Card Image Capacity

Here is a quick estimation of how many large JPEGs you could expect to store on an SD memory card.

  • 4GB - 1920 images
  • 8GB - 3840 images
  • 16GB - 7680 images
  • 32GB - 15360 images

Memory Card Speed

The speed rating for SD cards is established by the sequential read and write speeds. The speed of the SD card is important in the event that many shots need to be written or read from the card.

SD Card Speed Class Rating

SD Card Speed Class

The Class speed rating of an SD card is based on the sustained write speed of the SD card. A Class speed rating of 2 means that the SD card can maintain a write speed of at minimum 2MB per second.

  • Class 2 - 2MB/s
  • Class 4 - 4MB/s
  • Class 6 - 6MB/s
  • Class 8 - 8MB/s
  • Class 10 - 10MB/s

The top rating a memory card can have is Class 10. There are SD memory cards that are considerably faster than 10MB/s. Those memory cards use other technologies, such as UHS (Ultra Highspeed Bus), which have a separate rating standards.

Sustained write speeds of 2MB, 4MB, 6MB, or 8MB per second means the card has a speed class of 2, 4, 6, or 8. Cards that have write speeds of 10MB/s or faster are rated as Class 10.

MultiMediaCard Compatibility

Siemens AG and SanDisk unveiled the MultiMediaCard technical standard in 1997. MMC cards are close in dimensions to an SD card, but they are a little slimmer.

Only the first two generations of MMC cards will work correctly in the Canon SD940 IS. Compatible cards will be labeled as MMCplus or MMC. Later generations are not going to function in the Canon SD940 IS

It isn’t a good idea to buy any MMC cards. Compatible MMC cards for the SD940 IS are not currently being manufactured. Thus, they are quite challenging to come across pre-owned as well as being costly.


Buy an SD memory card for the Canon SD940 IS based on price. An expensive card isn’t going to improve performance. As long as it is a speed class 10 card, you will be fine. My recommendation is the PNY Elite 32GB SD memory card.