Published 20 minutes ago

Abhinav pivoted from a career in banking to pursue his first love in writing. Even while working full-time, he continued contributing as an editor-at-large, a role he has held for more than 7 years. A lifelong tech enthusiast who has built three gaming and productivity powerhouse PCs since 2018, his passion for technology keeps him closely following the semiconductor industry, from NVIDIA and AMD to ARM. His MSc dissertation explored how artificial intelligence will reshape the future of work, reflecting his curiosity about the wider social impact of emerging technologies.

I come from an era where you could find microSD cards almost everywhere. Inside Handycams, Sony Ericsson phones, BlackBerry handsets, MP3 players, and early smartphones long before internal storage became generous or affordable. For the longest time, they were the easiest way to carry your digital life in your pocket. In late 2025, they’re still very much alive for things such as powering game libraries on the Nintendo Switch, expanding storage on the Steam Deck, for Raspberry Pi projects, and even some security cameras, drones, and dashcams.

While convenient, cheap, and often good enough for what they’re designed to do, many aren’t aware that microSD cards are just not the right place for important data. Beyond how easy it is to lose them, there are architectural and physical reasons as to why microSD cards can fail, and there are challenges that make recovery very difficult, if not impossible. If your data matters, it shouldn’t exclusively live on a microSD card.

Monolithic architecture makes recovery a pain

Failure can also lead to permanent data loss

It’s not uncommon to presume that storage recovery works the same way across devices. When a drive fails, a data recovery expert can extract the memory chips and recover the data. That assumption, however, should not be applied to a micro SD architecture.

Unlike SSDs and hard drives, most modern microSD cards use what is known as a monolithic design. The controller and the NAND flash on this architecture are fused together on a single block of silicon and resin. Since there are no separate chips to isolate, there’s no way to bypass a failed controller, and therefore, no clean access points for data extraction. This makes it significantly harder to recover in the event of corruption.

If your card develops even a microscopic crack from bending, twisting, or improper handling, the internal traces are severed. When this happens, recovery is effectively impossible through user action. Even in professional data recovery circles, a cracked microSD card presents a very challenging recovery scenario. Even with expensive recovery methods like re-bonding, data retrieval is notoriously hard and not guaranteed.

Your data can expire in a drawer

Thanks to charge bleed

MicroSD cards store data by trapping electrons inside floating gate transistors. Over time, due to quantum tunneling, those electrons tend to leak. This happens with all flash-based storage like SSDs, but microSD cards are especially vulnerable due to their architecture.

Due to a combination of their extreme density, low-cost manufacturing methods, and limited error correction, charge leakage happens faster with even fewer safeguards than an SSD. If you regularly write photos, documents, or backups to a microSD card and leave it unpowered in a drawer for many years, the data can silently decay. Even if you remember where you stored them, you may discover that files have become corrupt or unreadable with no warning signs.

High-end SSDs mitigate this problem with stronger error correction and an active maintenance routine, but they’re still not quite immune to it, and believe it or not, it is going to take actual advancements in our understanding of quantum mechanics to eliminate this problem altogether (if there’s a cost-effective way to even do it). Luckily, the simpler solution is to just back up your data somewhere safer, like the cloud or an HDD.

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The ‘read disturb’ and passive wear problem

Even reading a microSD card has implications

There’s a common belief that storage only wears out when you write to it. While it holds true in the case of SSDs, which are rated only for a number of program/erase (P/E) cycles, there’s more to the story in the case of microSD cards.

On SD cards, repeatedly reading the same data can cause what’s known as ‘read disturb’. Each read operation applies a small electrical stress to nearby cells. Over time, this stress can shift the charge in adjacent cells, which can corrupt the data you weren’t even making changes to.

This problem is compounded by the inherent simplicity of microSD controllers. Unlike SSDs, they lack autonomous background management. They can’t proactively refresh stressed cells or relocate vulnerable data unless active writes occur. So, while an SSD would see the problem coming and intervene, a microSD card often won’t, and it just lets the data degrade in place, making it even less suitable for storing sensitive or important files.

Murphy’s Law applies a lot to storage, so don’t gamble with it

MicroSD cards still have an important place in modern tech. Their form factor makes it the perfect way to expand storage in portable devices, and that’s still very hard to beat or find a replacement for, unless you’re paying big tech for their cloud storage. They are excellent for game libraries and save files, disposable media, and devices where portability matters more than permanence.

What they’re not built for, however, is safeguarding irreplaceable photos, documents, or any form of backup. Their monolithic design makes recovery fragile, flash cells decay (even when left unpowered and unused), and their simple controller architecture lacks the sophistication to protect your data over extended periods of time. None of these failures has any obvious warning signs that you can look out for, which is precisely what makes your data vulnerable to loss. And as it happens, most of the time with storage, whatever can go wrong, *will *go wrong.