Is your USB flash drive trustworthy? These tips will tell you

Everyone knows them, everyone has them. USB sticks, or thumb drives, are ideal for quickly exchanging data between computers — but also for transporting digital content between mobile phones and PCs when the cloud is not an alternative.

Because they are so small, USB sticks are also very popular as promotional gifts or are quickly added to the shopping basket just before the checkout in the electronics store.

Trouble later arises because the stick turns out to be a bad buy. That’s why it’s worth knowing a little more about USB sticks. After all, we entrust our private and business data to these small data transporters.

The USB interface makes them universally applicable — with the Type A and Type C designs now available in two connector formats. The differences in the flash modules themselves are worth knowing.

It is also interesting to know which capacities and transfer speeds are now possible — and which are not.

Because only those who know why one USB stick is more expensive and what distinguishes it from the supposed bargain options will ultimately make the right choice for their own purposes.

Tip: You’re using your USB flash drive wrong. Do this instead

Differences in flash drives

Both USB SSDs and USB sticks use flash memory as their basis. The fundamental difference lies in the quality of the flash modules. They are manufactured in the same production facilities and may even come from the same machines.

However, they are not identical in quality. The best flash chips are generally used for the production of SSDs. The next quality level involves flash components for the production of memory cards — such as SD or MicroSD cards. This is followed by flash memory for USB sticks.

However, this does not automatically mean that every USB stick is of poor quality, per se. However, it does show that USB sticks are not designed for long-term archiving. It also makes it clear why USB 2.0 speed is still widely used for inexpensive USB sticks in particular.

Last year, a report by the company CBL Datenrettung also caused a stir: More and more USB sticks with inferior memory chips were ending up in the company’s laboratories.

The manufacturer logos on the NAND chips were missing or had been made unrecognizable. The capacity information was also incorrect. As a rule, the actual storage space was less than the label would have us believe.

Further reading: The best external drives

The data sticks examined were both promotional gifts and branded goods. The company concluded from this that more and more memory chips are ending up on the market that should actually have been decommissioned.

This observation emphasizes once again that USB sticks are not the right choice for sensitive storage tasks. You can find out how to treat the drive so that it provides good service for as long as possible in the box below “USB stick: Handling tips.”

Further reading: How long does data last on a USB flash drive? It’s complicated

Capacities of USB flash drives

If you look for USB flash drives on price comparison websites, you can usually specify the desired storage capacity. The selection range here is usually between 64GB and 1TB. And that’s a good thing. Because if you are offered significantly higher capacities for a USB stick, then the products are almost certainly counterfeits.

The most obvious clue is the price. If the price is exceptionally low for a 2TB stick — for example less than $10 — then all your alarm bells should be ringing.

If the online provider also comes from the Far East, the scam is obvious.

A healthy dose of skepticism is worthwhile when buying a USB stick to avoid trouble later on. In most cases, you will actually receive a drive with only 32GB or 64GB of flash memory.

At the same time, the boundaries between USB stick and USB SSD can become blurred with high capacities.

One example: While price search engines refer to the Adata SC610 2TB model as a USB stick, the data carrier is labelled by the manufacturer as an “external solid state drive” — in other words, an external SSD. The price of around $145 emphasizes the latter, but the form factor with USB-A interface directly on the housing gives the impression of a stick.

Nevertheless, it can be said that the majority of branded USB sticks are currently available in capacities of 64, 128, 256, and 512GB. An entry-level stick with 64GB currently costs around $10. For a 512GB model, you can expect to pay between $40 and $50.

Reading tip: Best USB-C cables 2025: Get quality charging and data transfers

Boot stick for Windows

There are always problems with Windows boot sticks. They are either not recognized or cannot be created in the first place. The problem is usually not the capacity. According to Microsoft, the official minimum requirement is 8GB. You are definitely on the safe side with a 64GB stick.

There are also a few points that you should bear in mind: In principle, the USB stick should ideally be new and unused, as this provides the freshest flash memory. It is also advisable not to use a USB stick that is too slow. It is better to avoid USB 2.0 models for the installation medium.

It is advisable to use a stick from a brand manufacturer such as Sandisk (Western Digital, WD), Samsung, Kioxia, Lexar, Kingston, or Crucial (Micron). Or from providers such as PNY, Adata, Hama, Intenso or Verbatim.

With cheap and no-name sticks, you cannot judge the quality of the components used.

A complaint in the event of a defect is also very likely to come to nothing. Basically, you can only hope that the retailer will refund the purchase price — but not that the retailer will stop selling the product.

Speed boost through USB standard

Not every new USB stick automatically provides a speed boost. Conversely, you will achieve the greatest boost in data transfer if you switch to a faster USB interface — provided your host device supports the standard.

USB 2.0: The slow USB 2.0 standard is still widespread, especially with very inexpensive models. Here you can only achieve a transfer rate of around 45MB/s even when reading. Write rates can even be as low as 10MB/s.

USB 3.2 Gen1: In many cases, the outdated designation USB 3.0 can still be found on USB stick packaging. The read transfer rates are at best 450MB/s, while the write rates can easily drop to less than half that. However, many sticks only achieve around 200MB/s.

USB 3.2 Gen2: This interface, formerly known as USB 3.1, has now become very established and can be present on the computer as both a Type-A and Type-C connector. This port is also extremely popular for USB accessories. Most external USB SSDs in which an NVMe data carrier is installed already rely on USB 3.2 Gen2.

USB sticks with this interface are also becoming increasingly popular, but are still on the rise and therefore expensive. Based on the interface standard, a bandwidth of 10Gb/s is available here.

In the best case scenario, data rates of around 1000MB/s can be achieved — again, the ideal case only applies to read tasks.

However, the presence of a Type C connector alone does not automatically signal that the promised maximum speed is supported.

For example, we tested the Verbatim Dual Quickstick model with 256GB capacity for this guide. It has both a Type A and a Type C connector and, according to the packaging, is supposed to support USB 3.2 Gen1.

The benchmark runs with CrystalDiskMark show that this is only the case with one connection: The drive actually achieves over 450MB/s read and write speeds via Type A. Via Type C, the transfers drop to a good 40MB/s. This makes it clear that only the much slower USB 2.0 speed is possible via Type C.

More space, perhaps more speed

The transfer rates stated by the manufacturers represent ideal values for sequential tasks. They can be verified with benchmark tools, but rarely occur in everyday life — most likely when copying a large file, such as a video.

The controllers used play an important role in achieving fast data transfers. If they can distribute the data to several memory modules at the same time, the stick can complete the tasks faster. The greater the capacity, the more flash modules are available. Sticks with a higher capacity can therefore also work faster.

Such controllers are not always built into the sticks. Very cheap versions, in particular, use chips that are not capable of simultaneous distribution. The work is then done one after the other: Only when one flash module is completely filled is it the next one’s turn.

This procedure slows down the process. Even sticks with a large capacity do not gain any speed.

File systems for USB sticks

USB sticks can be formatted ex works in different file systems. FAT32 (File Allocation Table) used to be very common. However, it has the disadvantage that it cannot handle file sizes over 4GB. Anyone who likes to drag videos onto the stick should bear this in mind.

An alternative is exFAT (Extensible File Allocation Table), which was specially developed for flash memory. It is the most popular file system for USB sticks. Its strength lies in its flexibility. For example, exFAT is compatible with both Windows and Mac OS and works with Android and iOS devices. This makes it easier to exchange data between PCs and mobile devices.

However, you need to be careful if you want to connect the USB stick to a smart TV. Many TVs can’t do anything with it, some are even exclusively set to FAT32.

Sometimes you will also encounter the NTFS (New Technology File System) file system on USB sticks. It is the Windows standard and therefore the first choice if you only want to use the stick with Windows systems. NTFS is also compatible with Chrome OS.