Everything You Should Know Before Buying an SD Card

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If you are worried about choosing the right SD card, don’t worry. In the following guide, you will learn everything there is to know about choosing an SD Card.

Understanding The Types of MicroSD Cards

Unfortunately, you can’t go to the store and ask for an SD card without researching first. What capacity do you want it to have? Or Is the SD card for your phone, camera, or tablet? 

If you look at an SD card right now, you will probably only notice if it’s a 16GB or 32GB card. There is more to an SD card than that, but most may not care about that. As long as it has the capacity you need, who cares about everything else?

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Grab the SD card again and give it another look. You will notice that it has two symbols. You will see a 2, 4,6, or 10, and the number will be inside a broken circle. Another symbol you see is the number 1 or 3 inside a U.

So, what do these symbols mean? They refer to the Speed Class that they are in. In other words, these symbols help you understand the minimum writing performance to guarantee that the video is written as smoothly as possible.

So next time you shop online and search for your next SD card, remember the following:

  • Class 2 – The Minimum serial data is 2MB/s
  • Class 4 – equals the minimum serial data being 4MB/s
  • Class 6 – With a minimum serial data is 6MB/s
  • Class 10 – Minimum serial data of 10MB/s

If you are looking for something other than something fancy and want something for your primary consumer, an SD card from classes 2-6 should be OK. They have an average writing speed you should be happy with.

High-Speed SD Cards

You’ll need a speed class UHS Card if you need speed and an SD card with high writing speeds. UHS means Ultra High Speed, and there are two to choose from. You can choose either a UHS 1 with a minimum serial data of 10MB/s or a UHS 3 card with a minimum serial data of 30MB/s.

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  • If you use your SD card to store HD and Full HD videos, you should be OK with a Class 4 or 6 SD card.
  • If you are going to use the SD card to save standard-quality videos, then you should be OK with a Class 4.
  • If you will store Full HD pictures from a digital camera and raw videos on your SD, then a Class 10 is the right choice. Regarding the UHC cards, the UHC 1 runs at 10MB/s and is perfect for full HD pictures and videos.
  • UHC 1 cards are also the least you can get when dealing with 2K content. Since UHS 3 cards run at 30MB/s, you can easily use them for 4K or 2K videos.

SD Cards with WiFi Support

If you are unfamiliar with the type of SD card, you might be surprised that some support WiFi. The benefit of these SD cards is that you can connect to a cloud service with a non-WiFi-enabled device.

You can easily save your images to the cloud, and rest assured that your photos are backed up.

Things to Consider Before Buying an SD Card with WiFi Support

Be Careful Not to Buy an Incompatible Card

You’re probably already familiar with some types of SD cards. Off the top of your head, you could name an SD, SDHC, or SDXC card. But there is more to SD cards than that.

It doesn’t matter if they are average-sized or of the micro SD format; both are based on the same spec. Remember that the SD spec characterizes the SD card format, but they will work in different ways.

In other words, the formats I have mentioned are not backward compatible. This means you can’t use a current SD card on a device that only supports older formats. That is why you must know the specs of your device and what it can and can’t help.

Let’s take a look at how much each format can support:

  1. MicroSD Card – Micro means extremely small. You usually use a MicroSD card on a device such as your smartphone.
  2. MicroSDHC – This format can hold files from 2GB to 32 GB. You can use this kind of card in a device that specifies that it can support SDCX or SDHC.
  3. MicroSDXC has a limit of up to 2 TB and a minimum of 32GB.

Things You Probably Don’t Know About SD Cards

  1. SD cards come in different sizes, and Full-sized SD cards will only work on laptops, computers, and digital cameras. The Mini SD cards are smaller but only compatible with fixed digital cameras, tablets, and larger devices.

If you need to expand your smartphone storage, then you need to get a MicroSD card. If you ever need to transfer your files to your computer, buy the correct adapter.

Remember that adapters will work with different SD cards in harmony with standard SD Card slots.

  1. The kinds of files you want to store will define the type of card you need to buy.
  1. Remember the transfer speed – The kind of SD card you get has to have enough writing speed for the type of files you have. If you want smooth playback for Full HD content, you can’t get a Class 2 SD card.
  • Class 2 Cards have basic speeds. 
  • Class 4 and 6 are for HD content. 
  • Class 10 is for Full HD content.
  1. If you’re only going to use your SD card for everyday use, then you should be OK with an SD card. You must remember that you can use an SD card on a device that supports SD and SDHC capacities. But, if you have a device that only supports SDHC and SDXC cards, you can’t buy a regular SD card.

What Beginners Should Look Out For

If you love taking pictures but don’t consider yourself a professional, you should be OK with an SD card that ranges from 8GB to 256 GB. If you go to the manufacturer’s sites, they usually have information showing you how many pictures you can save on the SD card.

Remember that the resolution, file type, and compression will determine how many videos and pictures you can save on the SD card.

5/5 - (4 votes)


Judy Sanhz
Judy Sanhz

I can never get enough of tech in general, whether it's Android or web apps, but helping others solve their tech problems also brings great satisfaction. I carry a device wherever I go and I'm always connected. Life without Internet just sounds too scary to me. :-).

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