If you run out of storage space on your phone or tablet, you’ll definitely want to find a way to get more. One of the simplest options is to insert a microSD card. Sadly, not all smartphones and tablets support microSD cards. If you have an iPhone or iPad, you’re out of luck. Fortunately, some of the best Android smartphones and tablets do support them, although if you’re the owner of a Samsung Galaxy S21, you might be disappointed to note Samsung has removed the microSD card slot in their latest flagship.
It’s best to fully understand how to use a microSD in order to get the most out of it. To see if your device accepts them, check the full specs for your phone on the manufacturer’s website or look for a microSD card slot in your phone. On newer phones, they’re generally part of the SIM tray.
There are a handful of things to consider when you’re choosing a new microSD card for your phone. Obviously, the price and capacity are going to be factors, but you also need to make sure that the type of card you buy is supported by your device and that it’s suitable for your needs.
SDHC and SDXC
SDHC stands for Secure Digital High Capacity, and SDXC stands for Secure Digital Extended Capacity. The only real difference is the range of data they can store. You’ll find that SDHC microSD cards range from 2GB to 32GB in size, while SDXC microSD cards can range from 32GB up to 2TB in size, though the biggest microSD card we’ve seen so far is 1TB.
Speed Class ratings
You’ll probably come across a slew of number-symbol combinations printed on cards and their packaging. These are Speed Class indicators that refer to a microSD card’s minimum sustained write speed. Write speed tells you how quickly data can be saved to the card and is expressed in megabytes per second (MBps). It’s useful to keep in mind when shopping for certain use cases like video recording. There are currently three classes: Speed Class, Ultra High Speed (UHS) Speed Class, and Video Speed Class. The original Speed Class is denoted by the write speed enclosed in a large “C,” while UHS Speed Class is shown with a Class number inside a large “U.” The mark for Video Speed Class is a stylized “V” followed by the write speed. Here’s how the minimum speeds for the different classes break down.
|Class||Minimum write speed|
|UHS 1||10 MBps|
|UHS 3||30 MBps|
Most reputable microSD cards these days will have at least a Class 10 rating for write speeds. These are just minimum requirements, and many cards are capable of faster speeds than their rating. A Class 10 card may offer 95 MBps, for example. Read or transfer speeds are likely to be respectable — around 100MBps — across many options as well.
Application Performance Class
The SD Association also has a standard called Application Performance Class, which is designed to highlight microSD cards that are suitable for use in smartphones and tablets. The A1 rating means that the card can manage random read input-output access per second (IOPS) of 1,500 and write IOPS of 500. The A2 rating indicates random read input-output access per second of 4,000 and write IOPS of 2,000. This is ideal for quickly opening apps and processing tasks. These A1 and A2 cards are worth looking out for if you intend to format your card as internal storage in an Android device, something Google calls “Adoptable Storage.”
Choosing a microSD card for your needs
If you are simply focused on adding storage space for downloaded files and casual pictures and videos, the lower Speed Class ratings will do just fine for your phone or tablet. Content creators shooting a lot of video will want to look for higher-end Class 10 and UHS microSD cards, at the very least. These will be better equipped to handle 4K resolutions and high frame rates of 60 frames per second or 120 fps. Android power users may want to consider cards with the App Performance Class designation.
In any case, you’re obviously going to want the highest speed, highest capacity microSD card you can get for the lowest price. We would advise you to factor in the brand reputation and the reported performance and reliability. Check out the warranty terms, just in case something should go wrong. You also need to be careful where you buy. If you’re going to use Amazon or eBay, then read some customer reviews and watch out for fake microSD cards because they’re disappointingly common.
We’ve picked out five of the best microSD cards for smartphones, from casual to professional use. You may want to look beyond this list, but we advise you to stick to well-known brands like Samsung, Lexar, SanDisk, Toshiba, and Kingston. All prices are correct at the time of writing, but the microSD card market moves fast, so expect them to change.
SanDisk Extreme 32GB
Here’s a speedy SDHC card that offers read speeds of up to 100 MBps and write speeds of up to 60 MBps. This is a durable card with a lifetime warranty in most regions, and the reviews are overwhelmingly positive. It will have no trouble with 1080p video and can even handle 4K, though you may want a larger capacity if that’s what you’re buying it for. It is certified UHS Speed Class 3, V30, and A1 for Adoptable Storage. It also comes with a handy SD adapter.
Samsung Evo Plus 64GB
This SDXC card is rated as UHS 3 and offers transfer speeds of up to 100 MBps. It’s a durable and reliable microSD card with a lot of positive reviews. It’s fast and efficient for use in phones and tablets and won’t have any trouble recording 1080p video, but you should opt for another card if you shoot in 4K. Ultimately, it’s a great all-arounder for a reasonable price.
Lexar Professional 128GB
For consumers looking for a fast-acting microSD card with a reasonable capacity, this Lexar card is a go-to option. The product is an SDXC card with a UHS 3 rating that also supports read speeds up to 270 MBps. This card can support 4K video recording with ease— just ensure the video has a minimum sustained write speed of 90 MBps. If you’re the friend who always seems to be filming videos on your mobile device, you’ll find that this card is an excellent match. And if our word isn’t enough, check out the sea of good reviews online backing it up.
Kingston Canvas Select Plus 256GB
This UHS 3 card is A1 rated, so it’s optimized for use in Android phones. It supports up to 256GB at a cost that fits many budgets, and it can easily support 1080p video recordings. Unfortunately, this card doesn’t have write speeds capable of executing 4K video recordings, but it does have improved read speeds up to 100 MBps. Your purchase also comes with an SD adapter.
PNY Pro Elite 512GB
If you’re not sure you need 1TB of storage — but 256GB seems like too little — this 512GB microSD card from PNY is the perfect middle ground. True, it’s not the fastest, with read speeds of up to 100 MBps and write speeds of up to 90MBps, but it’s a great option for your phone as it runs apps directly from the microSD card. Its U3 and V30 ratings mean it can handle 4K video, though if this is your main reason for buying the card, we recommend upgrading to the SanDisk Extreme 1TB instead. It’s also waterproof, shockproof, and magnet-proof, so it’s a great choice if you frequently switch your card between devices.
SanDisk Extreme 1TB
If your main priority is storage, then look no further than the 1TB option from the Sandisk Extreme line. This product comes with expanded storage options, and its UHS 3 and V30 Speed Class ratings both mean it’s capable of handling 4K video recording with ease. The card’s read speeds measure at about 160 MBps, and its write speeds reach up to 90 MBps. You’ll want to ensure your device is fully compatible with maximizing that potential performance. On top of all of these excellent performance features, the card also received one of the highest possible A2 ratings for its storage capabilities on Android devices.